Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

2003

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 7831 - 7860 of 9736

Full-Text Articles in Entire DC Network

Fleas And Lice Of Mammals In New Mexico, Paulette L. Ford, Richard Fagerlund, Donald W. Duszynski, Paul Polechla Jan 2003

Fleas And Lice Of Mammals In New Mexico, Paulette L. Ford, Richard Fagerlund, Donald W. Duszynski, Paul Polechla

Harold W. Manter Laboratory of Parasitology: Faculty Publications

All available records are compiled for three orders of ectoparasites of mammals in New Mexico: fleas (Siphonaptera), sucking lice (Anoplura), and chewing lice (Mallophaga). We have drawn from records at the University of New Mexico’s Museum of Southwestern Biology, the Vector Control Program of the New Mexico Environment Department, the Environmental Health Department of the City of Albuquerque, and several private collections. We list 99 species of fleas, 27 species of sucking lice, and two species of chewing lice. Included are appendices that list recorded ectoparasite species and their hosts in New Mexico and the counties …


The Blue Crab: Diseases, Parasites And Other Symbionts, Jeffrey D. Shields, Robin M. Overstreet Jan 2003

The Blue Crab: Diseases, Parasites And Other Symbionts, Jeffrey D. Shields, Robin M. Overstreet

Harold W. Manter Laboratory of Parasitology: Faculty Publications

A critical review of the microbial diseases, parasites, and other symbionts of the blue crab, Callinectes sapidus.


Cystic Echinococcosis In The Arctic And Sub-Arctic, Robert L. Rausch Jan 2003

Cystic Echinococcosis In The Arctic And Sub-Arctic, Robert L. Rausch

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The northern biotype of Echinococcus granulosus occurs throughout the holarctic zones of tundra and taiga, from eastern Fennoscandia to the Bering Strait in Eurasia and in North America from arctic Alaska approximately to the northern border of the United States. The cycle of the cestode is complex in taiga at lower latitudes, because of the greater diversity of potential hosts. In the Arctic and Subarctic, however, four patterns of predator/prey relationships may be discerned. Two natural cycles involve the wolf and wild reindeer and the wolf and elk (moose), respectively. Where deer of the two species coexist, both are prey …


A Pcr-Elisa For The Identification Of Cyathostomin Fourth-Stage Larvae From Clinical Cases Of Larval Cyathostominosis, J. E. Hodgkinson, J. Ralph Lichtenfels, T. S. Mair, P. Cripps, K. L. Freeman, Y. H. Ramsey, S. Love, J. B. Matthews Jan 2003

A Pcr-Elisa For The Identification Of Cyathostomin Fourth-Stage Larvae From Clinical Cases Of Larval Cyathostominosis, J. E. Hodgkinson, J. Ralph Lichtenfels, T. S. Mair, P. Cripps, K. L. Freeman, Y. H. Ramsey, S. Love, J. B. Matthews

Harold W. Manter Laboratory of Parasitology: Faculty Publications

We report the use of six oligoprobes designed from intergenic spacer region sequences to identify fourth-stage larvae (L4) of the tribe Cyathostominae. Oligoprobes were designed for identification of the following species: Cylicocyclus ashworthi, Cylicocyclus nassatus, Cylicocyclus insigne, Cyathostomum catinatum, Cylicostephanus goldi, and Cylicostephanus longibursatus. A seventh probe was designed as a positive control to identify all these members of the Cyathostominae. The intergenic spacer region was amplified by PCR using conserved primers. Initially, three oligoprobes were used in Southern blot analysis. To facilitate high-throughput identification, these and a further four oligoprobes were developed for use in a PCR–ELISA. …


Implementation Plan For The Conservation Of Nebraska’S Eastern Saline Wetlands, Ted Lagrange, Terry Genrich, Glenn Johnson, Dan Schulz, Brent Lathrop Jan 2003

Implementation Plan For The Conservation Of Nebraska’S Eastern Saline Wetlands, Ted Lagrange, Terry Genrich, Glenn Johnson, Dan Schulz, Brent Lathrop

Nebraska Game and Parks Commission: Publications

Nebraska’s Eastern Saline Wetlands are the most limited and endangered wetland type and vegetation community in the State and are considered critically imperiled in Nebraska. These wetlands provide habitat for a variety of native plant and animal species that depend on a saline environment, including two endangered species.

Because of their location in and around the city of Lincoln, saline wetlands are ideally located to provide recreational opportunities and flood protection. Past impacts have resulted in the degradation of nearly 90% of the saline wetlands and those remaining face continued threats.

Although several programs are in existence to address saline …


A Live Collection Of A Pistolgrip From Nebraska, Steven C. Schainost Jan 2003

A Live Collection Of A Pistolgrip From Nebraska, Steven C. Schainost

Nebraska Game and Parks Commission: Staff Research Publications

Freshwater mussels (Mollusca: Bivalvia: Unionidae) are one of Nebraska's more poorly known faunas. Studies have documented the presence of 31 species of which only 19 have been found either live or freshly dead. The remaining twelve species have only been found as weathered or subfossil shells, seven of which were considered to be extirpated including the pistolgrip (Tritogonia verrucosa). While a statewide survey never has been done there is distributional information available in several published papers and unpublished reports (Baxa 1981; Hoke 1983, 1994a, 1995, 1996, 1997; Roedel 1990; Lingle 1992; Freeman and Perkins 1992, 1997; Clausen and …


Focus Emu, December 2, 2003, Office Of Public Information Jan 2003

Focus Emu, December 2, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, November 4, 2003, Office Of Public Information Jan 2003

Focus Emu, November 4, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, December 16, 2003, Office Of Public Information Jan 2003

Focus Emu, December 16, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, April 29, 2003, Office Of Public Information Jan 2003

Focus Emu, April 29, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, April 15, 2003, Office Of Public Information Jan 2003

Focus Emu, April 15, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, March 11, 2003, Office Of Public Information Jan 2003

Focus Emu, March 11, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, July 8, 2003, Office Of Public Information Jan 2003

Focus Emu, July 8, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, February 4, 2003, Office Of Public Information Jan 2003

Focus Emu, February 4, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Focus Emu, August 12, 2003, Office Of Public Information Jan 2003

Focus Emu, August 12, 2003, Office Of Public Information

Focus EMU

No abstract provided.


Recovering Species Of Conservation Concern-Are Populations Expendable?, May Ruckelshaus, Paul Mcelhany, Michael J. Ford Jan 2003

Recovering Species Of Conservation Concern-Are Populations Expendable?, May Ruckelshaus, Paul Mcelhany, Michael J. Ford

United States Department of Commerce: Staff Publications

Simply mentioning the notion of species expendability may seem reprehensible, but it is a question raised often when conservation biology meets conservation practice, as in this volume. In particular, when arguing for the value of biodiversity, biologists are faced with the challenge of examining the roles that particular species might play in community function and whether there are redundancies in the functions of certain species. Does every species need to be conserved for our ecosystems to function? The question of expendability also is important in conservation planning that occurs at the species level: does every population need to be saved …


The Abundance Of Harbor Seals In The Gulf Of Alaska, Peter Boveng, John Bengtson, David Withrow, Jack Cesarone, Michael Simpkins, Kathryn Frost, John Burns Jan 2003

The Abundance Of Harbor Seals In The Gulf Of Alaska, Peter Boveng, John Bengtson, David Withrow, Jack Cesarone, Michael Simpkins, Kathryn Frost, John Burns

United States Department of Commerce: Staff Publications

The abundance of harbor seals (Phoca vitulina richardii) has declined in recent decades at several Alaska locations. The causes of these declines are unknown, but there is concern about the status of the populations, especially in the Gulf of Alaska. To assess the status of harbor seals in the Gulf of Alaska, we conducted aerial surveys of seals on their haul-out sites in August-September 1996. Many factors influence the propensity of seals to haul out, including tides, weather, time of day, and time of year. Because these “covariates” cannot simultaneously be controlled through survey design, we used a …


A Model Life Table For Bottlenose Dolphins (Tursiops Truncatus) From The Indian River Lagoon System, Florida, U.S.A., Megan K. Stolen, Jay Barlow Jan 2003

A Model Life Table For Bottlenose Dolphins (Tursiops Truncatus) From The Indian River Lagoon System, Florida, U.S.A., Megan K. Stolen, Jay Barlow

United States Department of Commerce: Staff Publications

Data gathered from 220 stranded bottlenose dolphins (Tzmiop tvuncatlls) in the Indian River Lagoon system, Florida, were used to derive a life table. Survivorship curves were fit to the data using Siler’s competing-risk model and a maximum likelihood approach. Population growth was estimated to be between r = 0.0 and 0.046 based on the observed numbers of stranded dolphins. Variance in survival rates was estimated using an individual-based, age-structured population projection model. We estimate that the overall annual mortality rate for this population was 9.8% per year. Sex-specific differences in survivorship were apparent with females outliving males. The …


Wolves And Humans, Steven H. Fritts, Robert O. Stephenson, Robert D. Hayes, Luigi Boitani Jan 2003

Wolves And Humans, Steven H. Fritts, Robert O. Stephenson, Robert D. Hayes, Luigi Boitani

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

TRY TO IMAGINE a small group of wolves sitting at a table engaged in vigorous debate. These wolves are from various parts of the globe and are perhaps a bit more scholarly than most. In fact, they are especially knowledgeable about the biology of that notorious two-legged species, Homo sapiens. They have been brought together to document their relationship with humans over the last several millennia. Pause for a few moments and consider what they might say ...

Perhaps the wolves' discussion would chronicle the evils of the human species, including details of atrocities committed against lupine ancestors down …


Wolves: Behavior, Ecology, And Conservation: Photo Section I, Douglas W. Smith, Rolf Peterson, L. David Mech, Barron Crawford Jan 2003

Wolves: Behavior, Ecology, And Conservation: Photo Section I, Douglas W. Smith, Rolf Peterson, L. David Mech, Barron Crawford

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Wolves in Yellowstone National Park's restored population often must compete with grizzly bears at the carcasses of their kills. Especially after their first feeding at a kill, wolves tend to relinquish their kills to bears. Photograph by Doug Smith.

Elk are one of the most common prey of wolves in the northern Rocky Mountains of North America, primarily because in most areas they tend to outnumber other prey. This large bull standing his ground escaped this pack. Photograph by Doug Smith.


Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft Jan 2003

Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft

United States Geological Survey: Publications

Field and laboratory studies were conducted in April and November 2002 to provide the first direct measurements of the benthic flux of dissolved (0.2-micrometer filtered) mercury species (total and methylated forms) between the bottom sediment and water column at three sampling locations within Camp Far West Reservoir, California: one near the Bear River inlet to the reservoir, a second at a mid-reservoir site of comparable depth to the inlet site, and the third at the deepest position in the reservoir near the dam (herein referred to as the inlet, midreservoir and near-dam sites, respectively; Background, Fig. 1). Because of interest …


Quantifying The Effects Of Small-Scale Heterogeneities On Flow And Transport In Undisturbed Cores From The Hanford Formation, M. N. Pace, M. A. Mayes, P. M. Jardine, T. L. Mehlhorn, John M. Zachara, B.N. Bjornstad Jan 2003

Quantifying The Effects Of Small-Scale Heterogeneities On Flow And Transport In Undisturbed Cores From The Hanford Formation, M. N. Pace, M. A. Mayes, P. M. Jardine, T. L. Mehlhorn, John M. Zachara, B.N. Bjornstad

United States Department of Energy: Publications

Accelerated migration of contaminants in the vadose zone has been observed beneath tank farms at the U.S. Department of Energy’s Hanford Reservation, Richland, WA. This paper focuses on quantifying hydrologic processes that control the fate and transport of contaminants in the unsaturated sediments beneath the Hanford tank farms. The experimental approach involved the use of field relevant, long-term unsaturated nonreactive transport experiments in undisturbed sediments from the Hanford Formation. Undisturbed sediment cores were collected from a laminated fine-grained sand unit within the Hanford Formation in both the vertical direction (flow cross bedding) and the horizontal direction (flow bedding parallel). Laboratory-scale …


Inhibition Of Bacterial U(Vi) Reduction By Calcium, Scott Brooks, James K. Fredrickson, Sue Carroll, David Kennedy, John M. Zachara, Andrew Plymale, Shelly Kelley, Kenneth Kemner, Scott Fendorf Jan 2003

Inhibition Of Bacterial U(Vi) Reduction By Calcium, Scott Brooks, James K. Fredrickson, Sue Carroll, David Kennedy, John M. Zachara, Andrew Plymale, Shelly Kelley, Kenneth Kemner, Scott Fendorf

United States Department of Energy: Publications

The rapid kinetics of bacterial U(VI) reduction and low solubility of uraninite (UO2,cr) make this process an attractive option for removing uranium from groundwater. Nevertheless, conditions that may promote or inhibit U(VI) reduction are not well-defined. Recent descriptions of Ca-UO2- CO3 complexes indicate that these species may dominate the aqueous speciation of U(VI) in many environments. We monitored the bacterial reduction of U(VI) in bicarbonate buffered solution in the presence and absence of Ca. XAFS measurements confirmed the presence of a Ca- U(VI)-CO3 complex in the initial solutions containing calcium. Calcium, at millimolar concentrations …


Adaptive Harvest Management: 2003 Duck Hunting Season Jan 2003

Adaptive Harvest Management: 2003 Duck Hunting Season

United States Fish and Wildlife Service: Publications

The process of setting waterfowl hunting regulations is conducted annually in the United States (Blohm 1989). This process involves a number of meetings where the status of waterfowl is reviewed by the agencies responsible for setting hunting regulations. In addition, the U.S. Fish and Wildlife Service (USFWS) publishes proposed regulations in the Federal Register to allow public comment. This document is part of a series of reports intended to support development of harvest regulations for the 2003 hunting season. Specifically, this report is intended to provide waterfowl managers and the public with information about the use of adaptive harvest management …


American Woodcock Population Status, 2003, James R. Kelley Jr. Jan 2003

American Woodcock Population Status, 2003, James R. Kelley Jr.

United States Fish and Wildlife Service: Publications

Singing-ground and Wing-collection surveys were conducted to assess the population status of the American woodcock (Scolopax minor). Singing-ground Survey data indicated that the number of displaying woodcock in the Eastern and Central Regions were unchanged from 2002 (P>0.1), although the point estimates of the trends were positive. Trends from the Singing-ground Survey during 1993-03 were –1.3 and –1.6% per year for the Eastern and Central regions, respectively (P<0.05). There were long-term (1968-03) declines (P<0.01) of 2.3% per year in the Eastern Region and 1.8% per year in the Central Region. The 2002 recruitment index for the Eastern Region (1.4 immatures per adult female) was the same as the 2001 index, but was 18% below the long-term regional average. The 2002 recruitment index for the Central Region (1.6 immatures per adult female) was 17% higher than the 2001 index (1.3 immatures per adult female), and was similar to the long-term regional average. The index of daily hunting success in the Eastern Region increased slightly from 1.8 woodcock per successful hunt in 2001 to 1.9 in 2002, but seasonal hunting success declined from 6.9 woodcock per successful hunter in 2001 to 6.6 in 2002. In the Central Region, the daily success index was 2.1 woodcock per successful hunt in 2001 and 2002; but seasonal hunting success increased from 10.0 woodcock per successful hunter in 2001 to 11.0 in 2002.


Native Weeds And Exotic Plants: Relationships To Disturbance In Mixed-Grass Prairie, Diane L. Larson Jan 2003

Native Weeds And Exotic Plants: Relationships To Disturbance In Mixed-Grass Prairie, Diane L. Larson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Disturbance frequently is implicated in the spread of invasive exotic plants. Disturbances may be broadly categorized as endogenous (e.g., digging by fossorial animals) or exogenous (e.g., construction and maintenance of roads and trails), just as weedy species may be native or exotic in origin. The objective of this study was to characterize and compare exotic and native weedy plant occurrence in and near three classes of disturbance – digging by prairie dogs (an endogenous disturbance to which native plants have had the opportunity to adapt), paved or gravel roads (an exogenous disturbance without natural precedent), and constructed trails (an exogenous …


Seasonal Distribution Of Migratory Tree Bats (Lasiurus And Lasionycteris) In North America, Paul M. Cryan Jan 2003

Seasonal Distribution Of Migratory Tree Bats (Lasiurus And Lasionycteris) In North America, Paul M. Cryan

United States Geological Survey: Staff Publications

Despite evidence of migration in North American tree bats (genera Lasiurus and Lasionycteris), details regarding seasonal movements in these widely distributed species are few. This study attempted to clarify patterns of seasonal distribution by mapping museum occurrence records by month. Monthly changes in the distribution of records indicate seasonal movements of tree bats. Northward migration during spring by Lasiurus cinereus appears to stem from wintering grounds in California and Mexico. During summer, male L. cinereus is mainly distributed in western North America, whereas females dominate samples from eastern regions. Lasiurus borealis winters in southeastern areas and expands its range …


Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle Jan 2003

Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle

United States Geological Survey: Staff Publications

The conterminous United States contains an extensive and generally well-studied record of Last Glacial loess. The loess occurs in diverse physiographic provinces, and under a wide range of climatic and ecological conditions. Both glacial and non-glacial loess sources are present, and many properties of the loess vary systematically with distance from loess sources. United States’ mid-continent Last Glacial loess is probably the thickest in the world, and our calculated mass accumulation rates (MARs) are as high as 17,500 g/m2/yr at the Bignell Hill locality in Nebraska, and many near-source localities have MARs greater than 1500 g/m2/yr. …


Eutrophication And Carbon Sources In Chesapeake Bay Over The Last 2700 Yr: Human Impacts In Context, John F. Bratton, Steven M. Colman, Robert R. Seal, Ii Jan 2003

Eutrophication And Carbon Sources In Chesapeake Bay Over The Last 2700 Yr: Human Impacts In Context, John F. Bratton, Steven M. Colman, Robert R. Seal, Ii

United States Geological Survey: Staff Publications

To compare natural variability and trends in a developed estuary with human-influenced patterns, stable isotope ratios (δ13C and δ15N) were measured in sediments from five piston cores collected in Chesapeake Bay. Mixing of terrestrial and algal carbon sources primarily controls patterns of δ13Corg profiles, so this proxy shows changes in estuary productivity and in delivery of terrestrial carbon to the bay. Analyses of δ15N show periods when oxygen depletion allowed intense denitrification and nutrient recycling to develop in the seasonally stratified water column, in addition to recycling taking place in surficial …


Survival Of The Western Pond Turtle (Emys Marmorata) In An Urban California Environment, Phillip Q. Spinks, Gregory B. Pauly, John J. Crayon, H. Bradley Shaffer Jan 2003

Survival Of The Western Pond Turtle (Emys Marmorata) In An Urban California Environment, Phillip Q. Spinks, Gregory B. Pauly, John J. Crayon, H. Bradley Shaffer

United States Geological Survey: Staff Publications

The western pond turtle Emys (formerly Clemmys marmorata) is declining throughout its range, primarily due to loss of habitat via urbanization and conversion to agriculture. Urban waterways present several important challenges to freshwater turtle populations, but they also present an opportunity to maintain declining species in a ubiquitous habitat that has high public visibility. The arboretum waterway on the University of California, Davis campus is an example of an extensively altered urban habitat that supports a relatively large E. marmorata population. Over the last 6 years, we monitored the turtle population inhabiting the arboretum waterway to determine the …