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

Digital Commons Network

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

Articles 1 - 8 of 8

Full-Text Articles in Entire DC Network

Factors Affecting Breeding Territory Size And Placement Of The Florida Grasshoper Sparrow (Ammodramus Savannarum Floridanus), Jill Aldredge Jan 2009

Factors Affecting Breeding Territory Size And Placement Of The Florida Grasshoper Sparrow (Ammodramus Savannarum Floridanus), Jill Aldredge

Electronic Theses and Dissertations

For most taxa, maximizing fitness depends on maintaining access to adequate resources. Territories provide exclusive use of resources for an individual or a family group, thus facilitating successful reproduction. The economic defensibility of a territory depends on the quality, abundance, and distribution of its resources as well as the amount of competition that an individual must endure to maintain exclusive access. The benefits of defense must outweigh the costs for territoriality to be profitable. Territory owners may benefit from territories with high quality resources, but they also may incur greater costs defending these resources from competitors. In contrast, territories with …


Factors Affecting Predation Of Marine Turtle Eggs By Raccoons And Ghost Crabs On Canaveral National Seashore, Fl, Justin Brown Jan 2009

Factors Affecting Predation Of Marine Turtle Eggs By Raccoons And Ghost Crabs On Canaveral National Seashore, Fl, Justin Brown

Electronic Theses and Dissertations

Changes in abundance of interactive species can have cascading, community-wide effects (Soule et al. 2003). Raccoons (Procyon lotor) prey on a competitor for marine turtle eggs, the Atlantic ghost crab (Ocypode quadrata). Conservation of marine turtles often includes managing raccoons-the most obvious egg predator-which may have broader ecological effects, and unknown effects on egg predation. Neither the relationship between raccoons and ghost crab density nor the effects of ghost crab density on egg predation are well understood. I studied raccoon-ghost crab interactions and the effects of environmental variation on their activity during the 2007 marine turtle nesting season on Canaveral …


The Effects Of Urbanization On The Structure, Quality, And Diversity Of Cypress Plant Communities In Central Florida, Courtney Knickerbocker Jan 2009

The Effects Of Urbanization On The Structure, Quality, And Diversity Of Cypress Plant Communities In Central Florida, Courtney Knickerbocker

Electronic Theses and Dissertations

The integrity of wetland ecosystems is largely determined by hydrological functionality, degree of connectivity to like ecosystems, and permeability to external influence. Land use changes in upland areas adjacent to wetland ecosystems may influence hydrology and connectivity while introducing novel biotic and abiotic materials. There is an increasing trend toward the use of remote assessment techniques to determine the degree of impact of external influences on adjacent wetlands. Remote assessment and predictive capabilities are provided by indices such as the Landscape Development Intensity Index (LDI) (Brown and Vivas 2005) which may be beneficial in determining site condition, and which have …


Habitat Use By The Southeastern Beach Mouse (Peromyscus Polionotus Niveiventris) At Cape Canaveral Air Force Station, Florida, Kathryn Simmons Jan 2009

Habitat Use By The Southeastern Beach Mouse (Peromyscus Polionotus Niveiventris) At Cape Canaveral Air Force Station, Florida, Kathryn Simmons

Electronic Theses and Dissertations

Successful recovery of the federally threatened southeastern beach mouse (Peromyscus polionotus niveiventris) depends in part on an understanding of their habitat requirements. I studied habitat use by beach mice at Cape Canaveral Air Force Station, Florida from March 2005 until March 2006. I livetrapped six grids, three on coastal dunes and three within scrub located inland from the coast. On each grid and trap station, I quantified the extent of bare ground, woody vegetation, non-woody vegetation, height of vegetation, and percentage of coarse sand in the surface soil. I assessed trap success relative to these habitat variables using linear and …


Landcover Change And Population Dynamics Of Florida Scrub-Jays And Florida Grasshopper Sparrows, David Breininger Jan 2009

Landcover Change And Population Dynamics Of Florida Scrub-Jays And Florida Grasshopper Sparrows, David Breininger

Electronic Theses and Dissertations

I confronted empirical habitat data (1994-2004) and population data (1988-2005) with ecological theory on habitat dynamics, recruitment, survival, and dispersal to develop predictive relationships between landcover variation and population dynamics. I focus on Florida Scrub-Jays, although one chapter presents a model for the potential influence of habitat restoration on viability of the Florida Grasshopper Sparrow. Both species are unique to Florida landscapes that are dominated by shrubs and grasses and maintained by frequent fires. Both species are declining, even in protected areas, despite their protected status. I mapped habitat for both species using grid polygon cells to quantify population potential …


Understanding Plant Community Composition In Agricultural Welands: Context Dependent Effects And Plant Interactions, Elizabeth Boughton Jan 2009

Understanding Plant Community Composition In Agricultural Welands: Context Dependent Effects And Plant Interactions, Elizabeth Boughton

Electronic Theses and Dissertations

Community composition results from an integrated combination of random processes, regional habitat spatial structure, local environmental conditions, and species interactions. For example, the outcome of plant interactions can change depending on local environmental conditions such as nutrient availability, land management, or herbivory intensity. In particular, plant interactions may vary between facilitation and competition depending on ecological context, with facilitation expected to be prevalent under stressful conditions. I present the results of four studies that address different aspects of the community assemblage and dynamics emphasizing the synergistic effect of different processes. In the first, I investigated the importance of habitat isolation …


Native Fire Regime As A Reference For Establishing Management Practices, Brean Duncan Jan 2009

Native Fire Regime As A Reference For Establishing Management Practices, Brean Duncan

Electronic Theses and Dissertations

Our understanding of natural fire regimes in human-dominated landscapes is limited. Fire regimes operating in the pyrogenic ecosystems of Florida have been altered by fire suppression and fuel fragmentation. This is especially true of North Merritt Island, Florida, where human impacts have led to an incomplete knowledge of current fire regimes. We know that growing season fires frequently occurred within general return intervals and that many native terrestrial species require fire to remain viable. A 20-year plus period of fire suppression caused structural and compositional changes to vegetation/fuels that led to catastrophic fires and the decline of native species populations …


Tissue Engineered Myelination And The Stretch Reflex Arc Sensory Circuit: Defined Medium Formulation, Interface Design And Microfabrication, John Rumsey Jan 2009

Tissue Engineered Myelination And The Stretch Reflex Arc Sensory Circuit: Defined Medium Formulation, Interface Design And Microfabrication, John Rumsey

Electronic Theses and Dissertations

The overall focus of this research project was to develop an in vitro tissue-engineered system that accurately reproduced the physiology of the sensory elements of the stretch reflex arc as well as engineer the myelination of neurons in the systems. In order to achieve this goal we hypothesized that myelinating culture systems, intrafusal muscle fibers and the sensory circuit of the stretch reflex arc could be bioengineered using serum-free medium formulations, growth substrate interface design and microfabrication technology. The monosynaptic stretch reflex arc is formed by a direct synapse between motoneurons and sensory neurons and is one of the fundamental …