Digital Commons Network^™

Microbial Biofilms: From Ecology To Molecular Genetics, Mary Ellen Davey, George A. O'Toole

Dartmouth Scholarship

Biofilms are complex communities of microorganisms attached to surfaces or associated with interfaces. Despite the focus of modern microbiology research on pure culture, planktonic (free-swimming) bacteria, it is now widely recognized that most bacteria found in natural, clinical, and industrial settings persist in association with surfaces. Furthermore, these microbial communities are often composed of multiple species that interact with each other and their environment. The determination of biofilm architecture, particularly the spatial arrangement of microcolonies (clusters of cells) relative to one another, has profound implications for the function of these complex communities. Numerous new experimental approaches and methodologies have been …

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

The Vascular Flora Of Prentice Cooper State Forest And Wildlife Management Area, Tennessee, John Trevor Beck

Masters Theses and Doctoral Dissertations

The vascular plants of Tennessee's Prentice Cooper State Forest and Wildlife Management Area were gathered from 112 collection trips made during the growing seasons of 1998 and 1999. Prentice Cooper has an interesting and a rich flora. I collected 2,313 specimens and examined 110 herbarium specimens. The flora is comprised of 139 families, 512 genera, and 1,038 species and lesser taxa. The four largest families are Asteraceae (128 species-12% of the flora), Poaceae (106 species-10%), Cyperaceae (64 species-6%), and Fabaceae (57 species-5%). These four families represent approximately 34% of the total flora. Numerous county extensions, as well as rare, threatened, …

Obituary: Elmer Clea Birney, 1940-2000, Hugh H. Genoways, Carleton J. Phillips, Jerry R. Choate, Robert S. Sikes, Kristin M. Kramer

University of Nebraska State Museum: Mammalogy Papers

On 11 June 2000, Dr. Elmer C. Birney unexpectedly passed away from cardiac arrest suffered while outside caring for his cattle at his home in Blaine, Minnesota. One of his former students, Robert Timm, probably best expressed the immediate reaction of his family and many friends: ‘‘He was too young and in too good of health to be gone so soon.’’ At the time of his death, Elmer was Professor in the Department of Ecology, Evolution and Behavior, the Curator of Mammals at the Bell Museum of Natural History, and Director of Graduate Studies of the program in Ecology, Evolution …

The Breeding Ecology Of White-Faced Ibis In The Lower Carson River Basin, Nevada, Eric Patrick Kelchlin

LSU Historical Dissertations and Theses

The Great Basin White-faced Ibis (Plegadis chihi) population is recognized as a Species of Management because of its small population size, limited number of traditional breeding sites, and vulnerability to habitat loss. The ability to predict future population trends and develop wetland management strategies is limited because many aspects of their breeding ecology and population dynamics are unknown. 1 examined White-faced Ibis nesting ecology and breeding habitat selection at the Lower Carson River Basin, Nevada, from 1995-1997, and the relationship between the local surface water conditions and trends in the number of breeding pairs from 1970-1997 on a local and …

The Use Of Border Collies In Avian And Wildlife Control Programs, Nicholas B. Carter

Wildlife Damage Management Conference

Airports attract large numbers of wildlife primarily because they offer immense tracts of foraging and nesting habitats free from the threat of predation. Border collies can serve as an effective means of wildlife control in these environments by introducing a predator into the ecosystem. Many wildlife dispersal methods seek to imitate predators or the effect of predators and become increasingly ineffective as wildlife habituate to the stimuli. However, border collies are true predators, representing an actual, not perceived, threat to wildlife thereby eliminating the problems of habituation. Six airports and military bases have initiated use of border collies at their …

Wildlife Damage In The Suburbs: Conflicts In A Human-Wildlife Landscape, Rebecca Field

Wildlife Damage Management Conference

The sprawling communities surrounding cities pose a paradox for wildlife. Suburban habitat, with parks, greenways, and planned open spaces, provide attractive habitat with abundant resources for some wildlife species. Yet the landscape is dominated by human activities and disturbances. Species with little tolerance for human disturbance and habitat changes have difficulty maintaining their populations in suburban environments. Yet more adaptable species flourish in suburban areas where there are less predators, increased food resources, and abundant habitat for cover and raising young. The resulting overabundant wildlife populations pose increasing problems for biologists, wildlife damage practitioners, and the public. Management of urban …

Fall 2000, Nsu Oceanographic Center

Currents

No abstract provided.

Nutrient Absorption And Utilization By Wing And Flight Muscle Morphs Of The Cricket Gryllus Firmus: Implications For The Trade-Off Between Flight Capability And Early Reproduction, Anthony J. Zera, Tammy Brink

Anthony Zera Publications

Absorption efficiency (AD, approximate digestibility, assimilation efficiency) of various macronutrients and conversion of absorbed nutrients to biomass (ECD) were compared among the two types of flightless morph and the flight-capable morph of the cricket, Gryllus firmus. No biologically significant phenotypic or genetic difference in AD for carbohydrate, protein or lipid was observed among morphs fed either a high-nutrient (100%) or a low-nutrient (25%) diet. Thus, previously-documented differences among adult morphs in carbohydrate and lipid content must be caused by processes other than variation in nutrient absorption by morphs during adulthood. Relative absorption efficiency of total dry mass of food …

Ard News August 2000

Agricultural Research Division: News and Annual Reports

CONTENTS:

Comments from the Dean
ARD Advisory Council Annual Report to Faculty
Natural Resouurces and Research Update
ARD Advisory Council Election Results
Anna Elliott Proposals
Sampson Range and Pasture Management Endowments
Sampson Range and Pasture Management Endowments
Widaman Trust Distinguished Graduate Assistant Award
Hardin Distinguished Graduate Fellowship for 2000-2001
National Research Initiative Report for 1999
Shear-Miles Fellowship 2000-2001
NRC Assessment of the National Research Initiative
USDA - ARS Research Leader Dr. Philip J. Schall
USDA Science and Education Impact Sheets
Congratulations to Faculty - Successful USDA Grant Proposals
Proposals Submitted for Federal Grants
New or Revised Projects
Grants and Contracts …

The Impact Of Lianas On Tree Regeneration In Tropical Forest Canopy Gaps: Evidence For An Alternative Pathway Of Gap‐Phase Regeneration, Stefan A. Schnitzer, James W. Dalling, Walter P. Carson

Biological Sciences Faculty Research and Publications

1 Regeneration in forest canopy gaps is thought to lead invariably to the rapid recruitment and growth of trees and the redevelopment of the canopy. Our observations, however, suggest that an alternate successional pathway is also likely, whereby gap‐phase regeneration is dominated by lianas and stalled in a low‐canopy state for many years. We investigated gap‐phase regeneration in an old‐growth tropical forest on Barro Colorado Island (BCI) in Panama to test the following two hypotheses: (i) many gaps follow a pathway in which they remain at a low canopy height and are dominated by lianas and (ii) the paucity of …

The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors

Biological Sciences Faculty Publications

Coastal marine ecosystems worldwide are being altered rapidly by the invasion of nonindigenous species. Unlike terrestrial and freshwater systems, the impacts of an invading species have never been quantified on multiple trophic levels for a marine food web. We measured the impact of the nonindigenous green crab, Carcinus maenas, on a coastal marine food web in central California and found that this predator exerted strong “top-down” control, significantly reducing the abundances of several of the 20 invertebrate species monitored over a 9-yr period. Densities of native clams, Nutricola tantilla and Nutricola confusa, and native shore crabs, Hemigrapsus oregonensis, showed 5-fold …

Molecular Evolution Of Insecticidal Spore-Forming Bacteria, John Pool

Honors Theses

Molecular methods are increasingly being used to determine the phylogeny of microorganisms. This research was intended to determine phylogenetic relationships for bacteria of the species Bacillus thuringiensis and other members of the Bacillus cereus group. Each strain was analyzed by its sasp-B gene sequence to determine its species classification and relation to other strains studied. Results of this study indicated that according to the sasp-B gene tree, the species Bacillus thuringiensis is a paraphyletic with respect to both Bacillus cereus and Bacillus anthracis. Some unexpected results and implications for species designations are also discussed.

Seasonal Comparison Of Remotely Sensed Relative Forest Ecosystem Temperature Zones With Topography And Forest Biomass In The Clear Springs Wilderness Area Of The Shawnee National Forest, Daniel Unger

Faculty Presentations

The use of thermal infrared data to delineate seasonal relative forest ecosystem temperature zones as a tool for forest ecological studies was analyzed. Analysis involved: (1) delineating relative seasonal forest ecosystem temperature zones within the Clear Springs Wilderness Area of the Shawnee National Forest using Landsat Thematic Mapper thermal infrared data; and, (2) quantifying the effect of topography and forest biomass on relative forest ecosystem temperature zones within seasons. Results indicate that slope was statistically uncorrelated with relative temperature zones within any season, aspect was statistically correlated with relative temperature zones during fall and winter, and forest biomass was statistically …

Feeding Habits Of Young-Of-Year Striped Bass, Morone Saxatilis, And White Perch, Morone Americana, In Lower James River, Va, Paul J. Rudershausen, Joseph G. Loesch

Virginia Journal of Science

A total of 188 young-of-year (YOY) striped bass, Morone saxatilis, and 199 YOY white perch, Morone americana, were collected by pushnet, seine and trawl during 24-hour periods from June through August, 1992 in lower James River, Virginia. The purpose was to identify prey and temporal and spatial feeding habits. Copepods were the most numerous prey of both species. Fishes and mysids comprised the largest volumetric percentage of diets of striped bass and white perch, respectively. Using an index of relative importance, leptodorids and copepods were the most important prey of striped bass and white perch, respectively. Both species …

Multiple Source Pools And Dispersal Barriers For Galápagos Plant Species Distribution, J. Alan Yeakley, John F. Weishampel

Environmental Science and Management Faculty Publications and Presentations

We reexamined geographic factors explaining the number of plant species on islands in the Galápagos Archipelago. We hypothesized that plant species richness (S) was related to the number of source pools and that plant species dispersal preferentially followed direct, oceanic pathways. To test different dispersal pathways from multiple source pools, the total number of islands within a given dispersal radius (i) was posed as the sum of the number of line-of-sight islands (C_i) and of the number of islands without line-of sight connection (B_i). In partial regression analyses, controlling for nearest island area (A₂) …

Estimating Animal Abundance Using Noninvasive Dna Sampling: Promise And Pitfalls, L. Scott Mills, J. J. Ciatta, K. P. Lair, M. K. Schwartz, D. A. Tallmon

Wildlife Biology Faculty Publications

Advances in molecular biology offer promise to the study of demographic characteristics of rare or hard-re-capture species, because individuals can now be identified through noninvasive sampling such as fecal collection or hair snags. However, individual genotyping using such methods currently leads to a novel problem that we call a "shadow effect," because some animals not captured previously are believed to be recaptures due to their DNA profile being an indistinguishable shadow of previously captured animals. We evaluate the impact of the shadow effect on the two methods most commonly used in applied population ecology to estimate the size of closed …

Arthropod And Helminth Parasites From The Plains Pocket Gopher, Geomys Bursarius Bursarius From The Hosts' Northern Boundary Range In Minnesota, Monroe H. Bartel, Scott Lyell Gardner

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

As part of a continuing and more general study of the diversity of parasites from subterranean mammals in central North America, individuals of the Plains pocket gopher, Geomys bursarius bursarius, were collected from 7 localities in northwestern Minnesota from September 1991 through October 1996. Arthropods collected included the fleas, Opisocrostis bruneri (4 of 124, 3.20/0), Foxella ignota ignota (85 of 124, 68.50/0); the chewing louse, Geomydoecus geomydis geomydis from 98 of 124 (790/0), and larvae of the tick, Dermacentor variabilis (1 of 124, 0.8%). Nematodes found included Physaloptera limbata (2 of 118 gophers, 1.7%), Capillaria americana (4 of 118, …

The Role Of Chitinase Production By Stenotrophomonas Maltophilia Strain C3 In Biological Control Of Bipolaris Sorokiniana, Zhongge Zhang, Gary Y. Yuen

Department of Plant Pathology: Faculty Publications

The role of chitinase production by Stenotrophomonas maltophilia strain C3 in biological control of leaf spot on tall fescue (Festuca arundinacea), caused by Bipolaris sorokiniana, was investigated in vitro and in vivo. The filtrate of a broth culture of C3, with chitin as the carbon source, was separated into fractions. A high molecular-weight fraction (>8 kDa) was chitinolytic and more inhibitory than a low-molecularweight, nonchitinolytic fraction to conidial germination and hyphal growth by B. sorokiniana and to leaf spot development. A protein fraction derived by ammonium sulfate precipitation and a chitinase fraction purified by chitin affinity …

Salinity And Shade Preferences Result In Ovipositional Differences Between Sympatric Tiger Beetle Species, W. Wyatt Hoback, Douglas A. Golick, Tina Marie Svatos, Stephen M. Spomer, Leon G. Higley

Department of Entomology: Faculty Publications

1. Adult tiger beetles of the genus Cicindela often co-occur within a habitat but larvae do not. Larvae are sedentary and form usually permanent burrows at the site of oviposition where they require 1-3 years for development.

2. To test niche partitioning based on ovipositional preference, the behavior of two sympatric salt marsh tiger beetles, Cicindela circumpicta and C. togata (Coleoptera: Cicindelidae), were examined.

3. In laboratory studies, female C. circumpicta and C. togata distinguished between experimental salinities, with the former preferring 4 parts per thousand (ppt) and the latter preferring 12 ppt. In the field, C. circumpicta larvae were …

The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne

Scholarship and Professional Work - LAS

Reptile species are declining on a global scale. Six significant threats to reptile populations are habitat loss and degradation, introduced invasive species, environmental pollution, disease, unsustainable use, and global climate change.

Delineating Relative Temperature Zones In Forest Ecosystems: An Adaptation And Evaluation Of Current Methodologies, Daniel Unger, J.J. Ulliman

Faculty Publications

The effectiveness of using: (1) thermal infrared data; (2) potential solar radiation: and. (3) predicted temperature for mapping relative temperature zones in forest ecosystems were evaluated as tools for forest ecology studies.

The computer simulation models SOLAR and MTCLIM were found to be ineffective for mapping relative forest ecosystem temperature zones. SOLAR-calculated potential solar radiation and MTCLIM-predicted temperature were found to be statistically uncorrelated with coincident mean maximum daily forest ecosystem ambient air temperature recorded within the University of Idaho Experimental Forest during June and July, 1993. Landsat Thematic Mapper thermal infrared data were shown to be effective for mapping …

Home Ranges Of Rat Snakes (Colubridae: Elaphe) In Different Habitats, Stephen J. Mullin, William H. N. Gutzke, Gary D. Zenitsky, Robert J. Cooper

Faculty Publications

Based on our findings, we suggest that rat snakes represent not only a major predator of kites, but also of other canopy and mid-story nesting species in the southeastern United States. For example, rat snakes are the most dominant snake nest predator of bird nests throughout the Southeast (DeGregorio et al. 2014) and are skilled tree climbers that often occupy arboreal habitats (Jackson 1976, Keller and Heske 2000, Sperry et al. 2009), particularly in bottomland forests (Mullin et al. 2000, Carfagno and Weatherhead 2009). Thus, the role of rat snakes as predators of nests above the understory is likely underappreciated …

Do Wolves Affect White-Tailed Buck Harvest In Northeastern Minnesota?, L. David Mech, Michael E. Nelson

USGS Northern Prairie Wildlife Research Center

We used simple linear regression to analyze 8-23 years of data on a wolf (Canis lupus) population and human harvest of white-tailed deer (Odocoileus virginianus) bucks in northeastern Minnesota to determine any effects of wolves on buck harvesting. Over the long term, wolves accounted for at least 14-22% inter-year variation in buck harvest in the region, but an unknown amount of variation in hunter effort have obscured any more precise estimate. For part of the area with poorest habitat, we found strong relationships (r² = 0.66-0.84) between annual wolf numbers and buck harvests from 1988 …

Toward An Ecosystem Approach To Remediation In The Great Basin, Ted K. Raab

Ted K. Raab

We consider the web of interactions among geologic materials, soils, plants, and animals to ask, "If mining or other extractive energy technologies occur in desert regions, what do we need to know to return the land to productivity?" The Great Basin represents a formidable challenge in this regard, as winters in these cold deserts and seasonal lack of moisture during parts of the year severely constrain the growing season for vegetation. Due to the nature of current or proposed mining activities in this region, we have chosen to concentrate on two potential pollutants: the trace element selenium (Se) and nitrate …

Biodiversity And Ecosystem Functioning: Importance Of Species Evenness In An Old Field, Brian J. Wilsey, Catherine Potvin

Brian J. Wilsey

Changes in land use, habitat fragmentation, nutrient enrichment, and environmental stress often lead to reduced plant diversity in ecosystems. However, it remains controversial whether these reductions in diversity will affect energy flow and nutrient cycling. Diversity has two components: species richness, or the number of plant species in a given area, and species evenness, or how well distributed abundance or biomass is among species within a community. We experimentally varied species evenness and the identity of the dominant plant species in an old field of Quebec to test whether plant productivity would increase with increasing levels of evenness, and whether …

Intraintestinal Sites Of Infection For The Trematode Species Plagitura Salamandra Holl 1928 And Plagitura Parva Stunkard 1933 In Red-Spotted Newts Notopthalmus V. Viridescens (Rafinesque), Jeremy T. Clay

Theses, Dissertations and Capstones

The red-spotted newt, Notopthalmus v. viridescens (Rafinesque) is a common salamander in the eastern United States. Studies on the parasites are available, however these studies examined total parasite fauna. This study examines two species, Plagitura salamandra Holl 1928 and Plagitura parva Stunkard 1933 found in the small intestine of the red-spotted newt. A total of 225 newts was collected and examined for the two Plagitura species. No difference was found in prevalence of infection, mean intensity, SVL, and weight between male and female newts. Plagitura parva was found in 24.4 % of the newts while P. salamandra was found in …

Center For Grassland Studies Newsletter, Winter 2000, Volume 6, No. 1

Center for Grassland Studies: Newsletters

Contents:

Genetically Enhanced Turfgrasses Where Are We Going? by Terrance Riordan, Department of Horticulture, University of Nebraska-Lincoln

NUBEEF Educational Web Site for Beef Producers by Rick Rasby, Department of Animal Science, University of Nebraska-Lincoln

Bison Symposium in Lincoln April 6-8

CGS Welcomes Laurice Matulka

GLCI Lists Benefits of Grazing Lands

Glickman Calls for National Commitment to Preserve Private Land

Nebraska Ranch Practicum Again Offered

2000 Nebraska Range Short Course by Lowell Moser, Department of Agronomy, UNL

Technology Spurs Alfalfa Genome Mapping

Field Trip Graduate Course Focuses on East Coast Ecology

April 1 Deadline for Abstracts: National Conference on Grazing Lands

Distribution And Habitat Of The Southern Two-Lined Salamander, Eurycea Cirrigera, In Will County, Illinois: Implications For Population Management And Monitoring, David Mauger, Timothy Bell, Eric L. Peters

Journal of the Iowa Academy of Science: JIAS

The southern two-lined salamander (Eurycea cirrigera) was found to occur at numerous localities within the Kankakee River State Park in Will County, Illinois. The species is restricted to small drainages within the Kankakee River valley that have flow consisting of groundwater that discharges at seeps or springs at or within the valley bluff. Cooler water temperatures and possibly other conditions that are associated with water derived from seep or spring sources may be important factors in determining salamander abundance. This is particularly relevant to larval habitat. These observations suggest that the spring or seep-fed larval habitat may be the primary …

Patterns Of Annual Seed Production By Northern Hemisphere Trees: A Global Perspective, Walter D. Koenig, Johannes M.H. Knops

School of Biological Sciences: Faculty Publications

We tested whether annual seed production (masting or mast fruiting) in Northern Hemisphere trees is an evolved strategy or a consequence of resource tracking by comparing masting patterns with those of annual rainfall and mean summer temperatures, two environmental variables likely to correlate with available resources. There were generally significant negative autocorrelations between the seed crop in year x and year x+1 (year x+2 in species of Quercus requiring 2 yr to mature acorns), as expected if resources are depleted in mast years in part by switching resources from growth to reproduction. Spatial autocorrelation in annual seed production generally declined …