Life Sciences Commons^™

The Paleoecology Of High-Elevation Bison In The Greater Yellowstone Ecosystem And Implications For Modern Bison Conservation, Darian Bouvier

Electronic Theses and Dissertations

The national mammal of the United States, the American Bison (Bison bison) was once nearly extinct. Populations have recovered to the degree that thousands roam the Great Plains today. Due to their large numbers and body size, this species has an oversized impact on the ecological communities where it lives and is considered a keystone herbivore in modern North American grasslands. This study explores the detailed, seasonally resolved, paleoecology of seven bison from the Greater Yellowstone Ecosystem during the Late Holocene through stable isotope analyses and species niche modeling. Isotopic analyses of δ¹³C, δ¹⁵N, …

Spatiotemporal Factors Affecting The Occupancy And Phenology Of A Declining Songbird (Bachman's Sparrow - Peucaea Aestivalis) At The Western Extent Of Its Range, Liam G. Wolff

Electronic Theses and Dissertations

The Bachman’s Sparrow (Peucaea aestivalis) is a declining songbird that occurs throughout the southeastern United States. Bachman’s Sparrow is a Species of Greatest Conservation Need in Texas, but information crucial to management efforts, such as factors affecting their detectability and occupancy, is lacking. I investigated the predictors of Bachman’s Sparrow occupancy and phenology in Texas using detections from autonomous recording units coupled with site characteristics and weather data. My results indicate that Bachman’s Sparrow occupancy is associated with increasing herbaceous ground cover and decreasing basal area, distance to the nearest source population, and basal area when canopy height …

Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura

Electronic Theses and Dissertations

The tallgrass prairie of North America has changed drastically since colonial settlement, with up to 99% of this region converted for agriculture and other land-uses. Concurrent with grassland conversion, grassland birds have experienced the most extreme, consistent, and widespread population declines of any avian guild. Agricultural lands in the U.S. Midwest were able to provide adequate habitat for several bird species until the 1950’s; however, altered and intensified management practices have degraded much of remaining suitable habitat and undermined ecosystem functions. Consequently, many grassland birds have been identified as Species of Greatest Conservation Need (SGCN) in many State Wildlife Action …

Examining The Northern Shrimp Fishery In A Changing Gulf Of Maine, Ashley N. Charleson

Electronic Theses and Dissertations

Northern Shrimp (Pandalus borealis) once supported a key commercial fishery in the State of Maine. Since its closure in 2013, the stock has remained in a particularly vulnerable state following recruitment failure, overfishing, and rising water temperatures. Furthermore, without this source of supplemental income, local fishermen have also experienced financial stress following unstable fishing conditions in other fisheries. The collective goal of this research project was to assess factors impacting the feasibility of reopening and maintaining this vulnerable winter fishery. These goals are addressed over 4 chapters. Chapter two offers insight regarding what is most often omitted from the regulatory …

Determining The Effects Of Plant Extracts And Saltro Nematicide On Hatching, Mortality And Reproduction Of The Soybean Cyst Nematode (Heterodera Glycines), Bishnu Prasad Dhital

Electronic Theses and Dissertations

Soybean cyst nematode (SCN) is a microscopic worm that infects and feeds from the soybean roots, hence robbing the plant of nutrients, and entry wounds may facilitate other pathogens to infect the roots. Current SCN management practices include cultural, chemical, and biological methods. Cultural practices such as, crop rotation with non-host and different tillage practices are not efficient due to the persistent nature of SCN in the soil. Chemical nematicides, though effective, can be expensive, and some are not environmentally sound. SCN resistant soybean varieties are mainly derived from one source, PI 88788 and SCN population have already evolved to …

Agronomic And Quality Response Of Hard Red Spring Wheat Genotypes To Management Systems In South Dakota, Jonathan Kleinjan

Electronic Theses and Dissertations

Intensive cereals management techniques such as multiple fungicide applications and in-season split N applications have been used to successfully improve wheat yields in Europe and in some winter wheat production areas of the USA. However, research on the effects of these management practices and their interaction with genotypes is limited in the hard red spring wheat (HRSW) production areas of the USA. The objectives of this study were to: (i) compare management treatments and (ii) quantify any interaction effects between management and genotype on the agronomic characteristics and relevant flour and dough properties of locally-adapted HRSW genotypes. A randomized complete …

The Effect Of Artificial Light Pollution On Orientation Of Hatchling Loggerhead Sea Turtles (Caretta Caretta) In The Grand Strand Region, South Carolina, Emily S. Asp

Electronic Theses and Dissertations

Sea turtle hatchlings primarily utilize sight to detect differences in elevation and light intensity present along the horizon to navigate from the nest to the water’s edge. The addition of artificial lights can cause visual misdirection, resulting in disorientation (aimlessly wandering in circular paths) or misorientation (moving in distinct paths away from ocean). Extensive research has been done on effects of high levels of artificial light but little on effects of comparatively lower levels of artificial light on hatchling sea turtle orientation. This study examined these lower intensity areas to identify if there is a threshold of artificial light above …

Financial Investment Management For Forest Sustainability, Zarina Ismailova

Electronic Theses and Dissertations

This is paper is discussion about main problems of forest management, whether financial investment has a substantial impact on the long term perspective of forest landscape restoration and, more specifically, what strategy and what financial options are available to make the forest projects more sustainable. A few relevant questions to ask are: who are the main actors in the implementation of FLR projects; which steps have to be taken; and, which financial options would more suitable and would be feasible to implement. There are three main parts of this research to be investigated:

1. forest issues along with their respective solutions, …

Species And Habitat Interactions Of The Gopher Tortoise: A Keystone Species?, Christopher Catano

Electronic Theses and Dissertations

Species-species and species-habitat interactions have been demonstrated to be important in influencing diversity across a variety of ecosystems. Despite generalities in the importance of these interactions, appropriate mechanisms to explain them are absent in many systems. In sandhill systems of the southeast U.S., gopher tortoises have been hypothesized to be a crucial species in the maintenance of diversity and function. However, the mechanisms and magnitude in which they influence their communities and habitats have rarely been empirically quantified. I examined how habitat structure influences tortoise abandonment of burrows and how tortoise densities influence nonvolant vertebrate community diversity. Tortoise burrow abandonment …