Reconstructing paleo lake levels from relict shorelines along the Upper Great Lakes
Steve J. Baedke, Todd A. Thompson, John W. Johnston, Douglas A. Wilcox
2004, Aquatic Ecosystem Health & Management (7) 435-449
Shorelines of the upper Great Lakes include many embayments that contain strandplains of beach ridges. These former shoreline positions of the lakes can be used to determine changes in the elevation of the lakes through time, and they also provide information on the warping of the ground surface that...
Modeling nest survival data: a comparison of recently developed methods that can be implemented in MARK and SAS
J. Rotella, S.J. Dinsmore, T.L. Shaffer
2004, Animal Biodiversity and Conservation (27) 187-205
Elements of a predictive model for determining beach closures on a real time basis: the case of 63rd Street Beach Chicago
Greg A. Olyphant, Richard L. Whitman
2004, Environmental Monitoring and Assessment (98) 175-190
Data on hydrometeorological conditions and E. coli concentration were simultaneously collected on 57 occasions during the summer of 2000 at 63rd Street Beach, Chicago, Illinois. The data were used to identify and calibrate a statistical regression model aimed at predicting when the bacterial concentration of the beach water was above...
Population demographics, survival, and reporduction: Alaska sea otter research
Daniel H. Monson, James L. Bodkin, D.F. Doak, James A. Estes, M. T. Tinker, D.B. Siniff
Daniela Maldini, Donald Calkins, Shannon Atkinson, Rosa Meehan, editor(s)
2004, Conference Paper, Alaska sea otter research workshop: Addressing the decline of the southwestern Alaska sea otter population
The fundamental force behind population change is the balance between age-specific survival and reproductive rates. Thus, understanding population demographics is crucial when trying to interpret trends in population change over time. For many species, demographic rates change as the population’s status (i.e., relative to prey resources) varies. Indices of body...
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...
Does presence of permanent fresh water affect recruitment in prairie-nesting dabbling ducks?
Gary L. Krapu, P.J. Pietz, D.A. Brandt, R. R. Cox Jr.
2004, Journal of Wildlife Management (68) 332-341
In the Prairie Pothole Region (PPR) of North Dakota, USA, American mink (Mustela vison) are a major predator of ducklings. Mink populations plummet during severe droughts, but some mink survive where permanent fresh water is available. In 1992–1993, we evaluated whether development of a permanent water body, the 125-km...
Changing perspectives on pearly mussels, North America's most imperiled animals
David L. Strayer, John A. Downing, Wendell R. Haag, Tim L. King, James B. Layzer, Teresa J. Newton, S. Jerrine Nichols
2004, BioScience (54) 429-439
Pearly mussels (Unionacea) are widespread, abundant, and important in freshwater ecosystems around the world. Catastrophic declines in pearly mussel populations in North America and other parts of the world have led to a flurry of research on mussel biology, ecology, and conservation. Recent research on mussel feeding, life history, spatial...
Effects of distance from cattle water developments on grassland birds
A.L. Fontaine, P.L. Kennedy, Douglas H. Johnson
2004, Journal of Range Management (57) 238-242
Many North American grassland bird populations appear to be declining, which may be due to changes in grazing regimes on their breeding areas. Establishment of water developments and confining cattle (Bos taurus L.) to small pastures often minimizes spatial heterogeneity of cattle forage consumption, which may lead to uniformity in...
Cannibalism and predation by western toad (Bufo boreas boreas) larvae in Oregon, USA
D.J. Jordan, C.J. Rombough, Christopher A. Pearl, B. McCreary
2004, Western North American Naturalist (64) 403-405
Larval amphibians have been widely used as model organisms in studies of community ecology of freshwater systems (Morin 1983, Alford 1999). Much of this work has assumed that trophic effects of larval anurans are focused on periphyton and planktonic algae (Dickman 1968, Seale 1980, Duellman and Trueb 1986), a view...
Optical characteristics of natural waters protect amphibians from UV-B in the U.S. Pacific Northwest: Reply
Wendy J. Palen, Daniel E. Schindler, M. J. Adams, Christopher A. Pearl, R. Bruce Bury, S. A. Diamond
2004, Ecology (85) 1754-1759
Few ecologists would dispute that exposure to high levels of ultraviolet-B radiation (UV-B) is detrimental to organisms. It is well established that UV-B has been a critical factor shaping the physiology (Blum et al. 1949, Hansson 2000), behavior (Pennington and Emlet 1986, van de Mortel and Buttemer 1998), and distribution (Williamson et...
Spatial and temporal multiyear sea ice distributions in the Arctic: A neural network analysis of SSM/I data, 1988-2001
G. I. Belchansky, David C. Douglas, I.V. Alpatsky, Nikita G. Platonov
2004, Journal of Geophysical Research (109)
Arctic multiyear sea ice concentration maps for January 1988-2001 were generated from SSM/I brightness temperatures (19H, 19V, and 37V) using modified multiple layer perceptron neural networks. Learning data for the neural networks were extracted from ice maps derived from Okean and ERS satellite imagery to capitalize on the stability of...
Estimating functional connectivity of wildlife habitat and its relevance to ecological risk assessment
A.R. Johnson, Craig R. Allen, K.A.N. Simpson
Lawrence Kapustka, Gregory R. Biddinger, Matthew Luxon, Hector Galbraith, editor(s)
2004, ASTM Selected Technical Papers STP1458
Habitat fragmentation is a major threat to the viability of wildlife populations and the maintenance of biodiversity. Fragmentation relates to the sub-division of habitat into disjunct patches. Usually coincident with fragmentation per se is loss of habitat, a reduction in the size of the remnant patches, and increasing distance between patches. Natural...
Use of radar remote sensing (RADARSAT) to map winter wetland habitat for shorebirds in an agricultural landscape
Oriane W. Taft, Susan M. Haig, Chris Kiilsgaard
2004, Environmental Management (33) 750-763
Many of todays agricultural landscapes once held vast amounts of wetland habitat for waterbirds and other wildlife. Successful restoration of these landscapes relies on access to accurate maps of the wetlands that remain. We used C-band (5.6-cm-wavelength), HH-polarized radar remote sensing (RADARSAT) at a 38° incidence angle (8-m resolution) to...
A unified approach to analyzing nest success
T.L. Shaffer
2004, The Auk (121) 526-540
Logistic regression has become increasingly popular for modeling nest success in terms of nest-specific explanatory variables. However, logistic regression models for nest fate are inappropriate when applied to data from nests found at various ages, for the same reason that the apparent estimator of nest success is biased (i.e. older...
Commentary: A cautionary tale regarding use of the National Land Cover Dataset 1992
Wayne E. Thogmartin, Alisa L. Gallant, Melinda G. Knutson, Timothy J. Fox, Manuel J. Suarez
2004, Wildlife Society Bulletin (32) 970-978
Digital land-cover data are among the most popular data sources used in ecological research and natural resource management. However, processes for accurate land-cover classification over large regions are still evolving. We identified inconsistencies in the National Land Cover Dataset 1992, the most current and available representation of land cover for...
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...
Comparison of catch and lake trout bycatch in commercial trap nets and gill nets targeting lake whitefish in northern Lake Huron
James E. Johnson, Mark P. Ebener, Kenneth Gebhardt, Roger Bergstedt
2004, Fisheries Research Report 2071
We compared seasonal lake whitefish catch rates, lake trout bycatch, and gearinduced lake trout mortality between commercial trap nets and gill nets in north-central Lake Huron. Onboard monitors recorded catches from 260 gill net and 96 trap net lifts from October 1998 through December 1999. Catch rates for lake whitefish...
Isolation of Snake River islands and mammalian predation of waterfowl nests
B.W. Zoellick, H.M. Ulmschneider, B.S. Cade, A.W. Stanley
2004, Journal of Wildlife Management (68) 650-662
In 1990–1992, we studied predation of waterfowl nests by mammalian predators on 30 islands in a 64-km reach of the Snake River in southwestern Idaho, USA, to identify river flows necessary to protect and enhance migratory bird use of Deer Flat National Wildlife Refuge. We monitored 235–314 Canada goose (Branta...
Migration of dispersive GPR data
M.H. Powers, C.P. Oden
Slob E.Yarovoy A.Rhebergen J.B., editor(s)
2004, Conference Paper, Proceedings of the Tenth International Conference Ground Penetrating Radar, GPR 2004
Electrical conductivity and dielectric and magnetic relaxation phenomena cause electromagnetic propagation to be dispersive in earth materials. Both velocity and attenuation may vary with frequency, depending on the frequency content of the propagating energy and the nature of the relaxation phenomena. A minor amount of velocity dispersion is associated with...
Use and interpretation of logistic regression in habitat-selection studies
Kim A. Keating, Steve Cherry
2004, Journal of Wildlife Management (68) 774-789
Logistic regression is an important tool for wildlife habitat-selection studies, but the method frequently has been misapplied due to an inadequate understanding of the logistic model, its interpretation, and the influence of sampling design. To promote better use of this method, we review its application and interpretation under 3...
Fire as a physical process
J. W. van Wagtendonk
N. G. Sugihara, J. W. van Wagtendonk, J. Fites-Kaufman, K. E. Shaffer, A. E. Thode, editor(s)
2004, Book chapter, Fire in California ecosystems
This chapter explores fire as a physical process, including combustion, fuel characteristics, fuel models, fire weather, ignition sources, mechanisms for fire spread, and fire effects. In wildland fuels, combustion occurs in three phases: preheating, gaseous, and smoldering. Fuel is characterized by physical and chemical properties that affect combustion and fire...
Effects of seeding ryegrass (Lolium multiflorum) on vegetation recovery following fire in a ponderosa pine (Pinus ponderosa) forest
Angela D. Barclay, Julio L. Betancourt, Craig D. Allen
2004, International Journal of Wildland Fire (13) 183-194
Forty-nine vegetation transects were measured in 1997 and 1998 to determine the impact of grass seeding after the 1996 Dome Fire, which burned almost 6900 ha of ponderosa pine (Pinus ponderosa Lawson) forest in the Jemez Mountains of north-central New Mexico. High- and moderate-burned areas in Santa Fe National Forest...
Biotic and abiotic factors related to rainbow smelt recruitment in the Wisconsin waters of Lake Superior, 1978-1997
Michael H. Hoff
2004, Journal of Great Lakes Research (30) 414-422
Lake Superior rainbow smelt (Osmerus mordax) recruitment to 12-13 months of age in the Wisconsin waters of Lake Superior varied by a factor of 9.3 during 1978-1997. Management agencies have sought models that accurately predict recruitment, but no satisfactory models had previously been developed. In this study, modeling was conducted...
Enhanced gas-phase transport in a deep unsaturated zone, Amargosa Desert (U.S.A.)
Michelle Ann Walvoord, David A. Stonestrom
Karel Kovar, Z. Hrkal, J. Bruthans, editor(s)
2004, Conference Paper, International conference on finite element models, MODFLOW, and more: Solving groundwater problems
No abstract available....
A quantitative approach to identifying predators from nest remains
R. Michael Anthony, J.B. Grand, T.F. Fondell, B.F. Manly
2004, Journal of Field Ornithology (75) 40-48
Nesting success of Dusky Canada Geese (Branta canadensis occidentalis) has declined greatly since a major earthquake affected southern Alaska in 1964. To identify nest predators, we collected predation data at goose nests and photographs of predators at natural nests containing artificial eggs in 1997-2000. To document feeding behavior by nest...
