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A Qualitative Analysis Of Differential Equations Of Population Dynamics, Kevin Brenner

Honors Theses, 1963-2015

An exploration of systems of equations modeling closed hypothetical ecosystems. Models are formed from biological assumptions about population. Models are constructed by combining or modifying simpler systems. The simple models used in constructing systems are the logistic, competition, and Lotka-Volterra models. Eigenvalues and eigenvectors are used to prove some results about the equilibria of the systems. Geometric perspectives of the systems are used to develop the intuitive approach of the work. Examples of graphed systems are included. Partial results are proven. Conjectures are formed. Difficulties in the work are described and suggestions for further work are given.

Red Imported Fire Ant Impact On Wildlife: An Overview, Craig R. Allen, Stephen Demarais, R. Scott Lutz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We reviewed the past 50 years of literature concerning red imported fire ant impacts on wildlife species. The red imported fire ant has had a negative impact on numerous species of wildlife. However, experimental evidence of population-level impacts is meager. We discuss potential fire ant perturbations and suggest research directions that may settle the long-standing controversy concerning the impact of imported fire ants on native vertebrates and the ecosystems they have invaded.

Winter 1994, Nsu Oceanographic Center

Currents

No abstract provided.

Summer 1994, Nsu Oceanographic Center

Currents

No abstract provided.

Armadillo (Dasypus Novemcinctus), Donald W. Hawthorne

Prevention and Control of Wildlife Damage Handbook

The armadillo (Dasypus novemcinctus) is a rather interesting and unusual animal that has a protective armor of “horny” material on its head, body, and tail. The armadillo ranges from south Texas to the southeastern tip of New Mexico, through Oklahoma, the southeastern corner of Kansas and the southwestern corner of Missouri, most of Arkansas, and southwestern Mississippi. The armadillo prefers dense, shady cover such as brush, woodlands, forests, and areas adjacent to creeks and rivers. More than 90% of the armadillo’s diet is made up of insects and their larvae. The armadillo is active primarily from twilight through …

Bird Damage At Aquaculture Facilities, W. Paul Gorenzel, Fred S. Conte, Terrell P. Salmon

Prevention and Control of Wildlife Damage Handbook

Reduction of the damage caused by fish-eating birds requires accurate bird identification and some knowledge of avian biology and habits. The open-water areas and large concentrations of aquatic livestock at aquaculture facilities are natural attractants to many birds. Birds can have a significant economic impact on the culture of aquatic products including fish, shellfish, crustaceans, and other invertebrates. For our purpose here, we will refer to these birds as fish-eating birds, and the aquatic products as fish.

Magpies, Thomas C. Hall

Prevention and Control of Wildlife Damage Handbook

Magpies (Pica pica and P. nuttalli) have lived in close association with humans for centuries. Magpies are found in western North America. Magpies are associated with the dry, cool climatic regions of North America. Magpies are omnivorous and very opportunistic, a characteristic typical of other corvids. Magpies, like other corvids, are intelligent birds. Magpies have come into conflict with humans in North America for quite some time. Magpies are protected as migratory nongame birds under the Federal Migratory Bird Treaty Act.

European Starlings, Ron J. Johnson, James F. Glahn

Prevention and Control of Wildlife Damage Handbook

Starlings (Sturnus vulgaris) are robin-sized birds weighing about 3.2 ounces (90g). Since their introduction into New York in the 1890s, starlings have spread across the continental United States, northward to Alaska and the southern half of Canada, and southward into northern Mexico. Starlings are found in a wide variety of habitats including cities, towns, farms, ranches, open woodlands, fields, and lawns. Starlings consume a variety of foods, including fruits and seeds of both wild and cultivated varieties. European starlings were brought into the United States from Europe. Starlings are frequently considered pests because of the problems they cause, …

Backfilling Canals To Restore Wetlands: Empirical Results In Coastal Louisiana, R. Eugene Turner, James M. Lee, Christopher Neill

Faculty Publications

Wetland restoration is largely a developing science and engineering enterprise. Analyses of results are too few and constrained to observations over a few years. We report here on the effectiveness of one restoration technique used sparsely in coastal Louisiana for several decades. Canals have been dredged in coastal Louisiana wetlands since 1938 for oil and gas exploration and extraction. These canals are typically dredged to 2.5 m depth and are 20 to 40 m wide. Canal lengths vary from 100 m to several 1000s m in the case of outer continental shelf pipeline canals that cross the wetlands.

Today, thousands …

Red Mud : Cutting Pollution And Boosting Yields, Rob Summers

Journal of the Department of Agriculture, Western Australia, Series 4

A by-product from the refining of bauxite ore in the South-West is proving a bonus for agriculture.

When spread over the land, not only is it improving soil quality, but it is helping to prevent leaching of phosphorus and the consequent massive algal blooms in the waterways.

Bauxite residue is also showing considerable promise in human and animal effluent disposal systems, composting urban refuse, sewage treatments and as a road base.

Western Australia is now in the forefront of this research which is attracting world-wide interest.

1994 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 1994.

1994 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 1994.

Flash Pyrolysis-Gas Chromatography/Mass Spectrometry Of Lower Kittanning Vitrinites: Changes In The Distributions Of Polyaromatic Hydrocarbons As A Function Of Coal Rank, Michael A. Kruge, David F. Bensley

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Chemical analyses restricted to a single coal maceral permit a focus on rank effects without concern for variations in organic matter type. Vitrinite concentrates of high purity were isolated from coal samples of the Lower Kittanning seam by multi-step density gradient centrifugation, with reflectances ranging from 0.66 to 1.39% Rmax. In addition to the previously recognized losses of phenolic compounds, the vitrinite pyrolyzates exhibit marked increases in relative concentrations of tri- and tetraaromatic hydrocarbons (especially benzo[a]fluorene, methyl-phenanthrenes, methylfluorenes and methylchrysenes) above 0.9% Rmax, i.e., beyond the "second coalification jump" of Teichmüller. Thus, petrographically-recognizable physical transformations are shown …

Effects Of Competition And Predation On Prothonotary Warblers And House Wrens Nesting In Eastern Iowa, Timothy Brush

Journal of the Iowa Academy of Science: JIAS

In a fragmented midwestern floodplain forest, a small Prothonotary Warbler (Protonotaria citrea) population experienced high competition with House Wrens (Troglodytes aedon) and mammalian nest predation in 1988-89. Despite the provision of 3 types of nest boxes and higher water levels, Prothonotary Warblers did not nest successfully and decreased in the fragmented forest in 1990-91. House Wrens used >90% of the nest boxes in both years. Wren territories doubled within the nestbox area, while remaining constant on an unmanipulated area. In contrast, a larger warbler population had high nesting success during 1990-91 in a relatively unfragmented, wetter forest tract. Such forests, …

Age And Developmental History Of Iowa Fens, C. A. Thompson, E. A. Bettis Iii

Journal of the Iowa Academy of Science: JIAS

Iowa fens are small, mineorotrophic peatlands maintained by shallow groundwater. Eighteen fen sites located across northern Iowa were mapped and radiocarbon dated to assess the timing of initial peat accumulation. The radiocarbon ages span the Holocene, ranging from 1,240 to 10,900 B.P.; however most fens postdate 5,000 yr B.P. The dominance of late-Holocene ages suggests that Holocene climatic change may have strongly influenced the record of peat accumulation. During the mid-Holocene Iowa was warmer and drier than at present, and peat was degraded or accumulated slowly in fens. The range of ages also implies that the commencement and subsequent rate …

Nomenclatural Changes For Some Diatoms Found In Iowa, David B. Czarnecki

Journal of the Iowa Academy of Science: JIAS

Nomenclatural revisions for four diatom taxa found in Iowa, two of which are presently maintained in the Loras College Freshwater Diatom Culture Collection (FDCC), are necessary because of systematic interpretations of the Division Bacillariophyta. Achnanthidium hauckianum (Grun.) Czarnecki comb. nov. was originally assigned to the genus Achnanthes Bory. Three taxa were previously assigned to the morphologically diverse genus Navicula Bory. These are Cavinula weinzierlii (Schimanski) Czarnecki comb. nov., Craticula cuspidata var. major [(Meist.) Czarnecki comb. nov. and] Craticula halophila var. subcapitata (0str.) Czarnecki comb. nov.

Synthesis Of Malathion, Malaoxon, And Isomalathion Enantiomers And Examination Of Their Interactions With Acetylcholinesterase, Clifford E. Berkman

Dissertations

No abstract provided.

Identification And Assessment Of Wildlife Damage: An Overview, Richard A. Dolbeer, Nicholas R. Holler, Donald W. Hawthorne

Prevention and Control of Wildlife Damage Handbook

Wildlife management is often thought of in terms of protecting, enhancing, and nurturing wildlife populations and the habitat needed for their wellbeing. However, many species at one time or another require management actions to reduce conflicts with people or with other wildlife species. Examples include an airport manager modifying habitats to reduce gull activity near runways, a forester poisoning pocket gophers to increase tree seedling survival in a reforestation project, or a biologist trapping an abundant predator or competing species to enhance survival of an endangered species.

Wildlife damage control is an increasingly important part of the wildlife management profession …

Raccoons (Procyon Lotor), Edward K. Boggess

Prevention and Control of Wildlife Damage Handbook

The raccoon (Procyon lotor) is found throughout the United States, with the exception of the higher elevations of mountainous regions and some areas of the arid Southwest. Raccoons prefer hardwood forest areas near water. Raccoons are omnivorous, eating both plant and animal foods. Raccoons may cause damage or nuisance problems in a variety of ways, and their distinctive tracks often provide evidence of their involvement in damage situations. Raccoons are protected furbearers in most states, with seasons established for running, hunting, or trapping.

River Otters (Lutra Canadensis), Edward P. Hill

Prevention and Control of Wildlife Damage Handbook

River otters (Lutra canadensis) are best known for their continuous and playful behavior, their aesthetic value, and the value of their durable, high-quality fur. River otters occur throughout North America except the arctic slopes, the arid portions of the Southwest, and the intensive agricultural and industrialized areas of the midwestern United States. The diet of the river otter throughout its range is primarily fish. The reproductive biology of river otters and all other weasels is complex because of a characteristic known as delayed implantation. The presence of river otter(s) around or in a fish hatchery, aquaculture, or fish …

Skunks, James E. Knight

Prevention and Control of Wildlife Damage Handbook

The skunk (Mephitis mephitis and Spilogale putorius), a member of the weasel family, is represented by four species in North America. The skunk has short, stocky legs and proportionately large feet equipped with well-developed claws that enable it to be very adept at digging. The striped skunk is common throughout the United States and Canada. Adult skunks begin breeding in late February. Skunks inhabit clearings, pastures, and open lands bordering forests. Skunks eat plant and animal foods in about equal amounts during fall and winter. Skunks become a nuisance when their burrowing and feeding habits conflict with humans. …

Wolves (Canis Lupus), William J. Paul, Philip S. Gibson

Prevention and Control of Wildlife Damage Handbook

Two species of wolves occur in North America, gray wolves (Canis lupus) and red wolves (Canis rufus). During the 1800s, gray wolves ranged over the North American continent as far south as central Mexico. Gray wolves occupy boreal forests and forest/agricultural edge communities in Minnesota, northern Wisconsin, and northern Michigan. Mech reported that gray wolves prey mainly on large animals including white-tailed deer, mule deer, moose, caribou, elk, Dall sheep, bighorn sheep, and beaver. Gray wolves are highly social, often living in packs of two to eight or more individuals. The ability of wolves to kill …

Bats (Myotis Lucifugus), Arthur M. Greenhall, Stephen C. Frantz

Prevention and Control of Wildlife Damage Handbook

Despite their ecological value, bats (Myotis lucifugus) are relentlessly and unjustifiably persecuted. Bats, the only mammals that truly fly, belong to the order Chiroptera. Bats in North America are virtually all insectivorous, feeding on a variety of flying insects (exceptions among house bats were noted previously). Most North American bats emit high frequency sounds (ultrasound) inaudible to humans and similar to sonar, in order to avoid obstacles, locate and capture insect prey, and to communicate. Bats often fly about swimming pools, from which they drink or catch insects. Bats use roosting niches that are indoors (human dwellings, outbuildings, …

Deer, Scott R. Craven, Scott E. Hygnstrom

Prevention and Control of Wildlife Damage Handbook

Deer (Odocoileus virginianus) are probably the most widely distributed and best-recognized large mammals in North America. Deer are even-toed ungulates of the family Cervidae. The white-tailed deer is found in every state in the United States except perhaps Alaska and Utah. Deer are creatures of the forest edge rather than the dense, old-growth forest. Browse (leaves, stems, and buds of woody plants) is generally available all year and is a staple food for deer. Breeding occurs from October to January depending on latitude. Deer damage a wide variety of row crops, forage crops, vegetables, fruit trees, nursery stock, …

Elk, David S. Decalesta, Gary W. Witmer

Prevention and Control of Wildlife Damage Handbook

The elk is a large, powerful animal with an adult weight averaging over 400 pounds (180 kg). The Rocky Mountain elk (Cervus elaphus nelsoni) is found in the Rocky Mountain states and in scattered locations in the Midwest and East. Although elk once roamed freely into lower elevation grasslands, they are now found primarily close to heavily forested areas that are dotted with natural or human-made (clear-cut) openings. Elk graze on grasses and forbs, and browse on shrubs, tree seedlings, and saplings. Weather and human activities influence elk activity. Elk commonly impact agricultural resources by competing with domestic …

Pronghorn Antelope (Antilocapra Americana), Sanford D. Schemnitz

Prevention and Control of Wildlife Damage Handbook

The pronghorn (Antilocapra americana) is not a true antelope but in a family by itself (Antilocapridae). It is native only to North America. Pronghorns currently have a scattered but widespread distribution throughout western North America. Pronghorns thrive in short and mixed grasslands and sagebrush grasslands. Pronghorns eat a variety of plants, mostly forbs and browse. Pronghorns depend on their eyesight and speed to escape enemies. Pronghorns sometimes cause damage to grain fields, alfalfa, and haystacks during the winter. Pronghorns have game-animal status in all of the western states.

Cottontail Rabbits, Scott R. Craven

Prevention and Control of Wildlife Damage Handbook

Rabbits (Sylvilagus floridanus) usually can be accepted as interesting additions to the backyard or rural landscape if control techniques are applied correctly. Under some unusual circumstances, control of damage may be difficult. There are 13 species of cottontail rabbits (genus Sylvilagus), nine of which are found in various sections of North America north of Mexico. The eastern cottontail’s range includes the entire United States east of the Rocky Mountains and introductions further west. Cottontails do not distribute themselves evenly across the landscape. Rabbits live only 12 to 15 months, and probably only one rabbit in 100 lives …

American Crows, Ron J. Johnson

Prevention and Control of Wildlife Damage Handbook

The American crow (Corvus brachyrhynchos) is one of America’s best-known birds. American crows are widely distributed over much of North America. American crows do best in a mixture of open fields where food can be found and woodlots where there are trees for nesting and roosting. Crows are omnivorous, eating almost anything, and they readily adapt food habits to changing seasons and available food supply. Crows are among the most intelligent of birds. Experiments indicate that American crows can count to three or four, are good at solving puzzles, have good memories, employ a diverse and behaviorally complex …

Gulls, Victor E. F. Solman

Prevention and Control of Wildlife Damage Handbook

The term gull refers to members of a group of 23 North American bird species that belong to the family Laridae, subfamily Larinae. The herring (Larus argentatus) and ringbilled (L. delawarensis) gulls are the most common and widespread of the species. Most gulls nest in colonies on sand and gravel-covered shorelines and islands. Gulls feed on land or water on aquatic animals, terrestrial invertebrates and small vertebrates, plant remains, carrion, and refuse. Increasing gull populations in North America during the past century have led to a variety of problems for different segments of society.

Swallows, W. Paul Gorenzel, Terrell P. Salmon

Prevention and Control of Wildlife Damage Handbook

Eight members of the swallow family Hirundinidae breed in North America: the tree swallow (Tachycineta bicolor), violet-green swallow (T. thalassina), purple martin (Progne subis), bank swallow (Riparia riparia), northern rough-winged swallow (Stelgidopteryx serripennis), barn swallow (Hirundo rustica), cave swallow (Hirundo fulva), and the cliff swallow (H. pyrrhonota). Cliff and barn swallows are found throughout most of North America. Four basic conditions are found near most cliff and barn swallow nest sites: (1) an open habitat for foraging, (2) a suitable surface for …