Ecology and Evolutionary Biology Commons^™

The Ecological Role Of Rhizophytic Green Algae In Soft-Bottom Habitats, Laura Bedinger

USF Tampa Graduate Theses and Dissertations

Rhizophytic algae are large, abundant primary producers throughout tropical and subtropical areas worldwide where they grow as an understory in seagrass beds, as well as form mixed or monospecific beds of exclusively rhizophytic algal species. In this dissertation, "rhizophytic algae" refers to coenocytic green algae (Chlorophyta) in the order Bryopsidales that use a net of rhizoids to anchor in unconsolidated sediments. In the development of seagrass beds, rhizophytic algae colonize bare patches and are thought to facilitate seagrass colonization by stabilizing sediments and providing organic matter. However, despite their prominence little is known about many aspects of the ecology of …

Paleobiological Assessment Of Controls Underlying Long-Term Diversity Dynamics, Andrés L. Cárdenas

USF Tampa Graduate Theses and Dissertations

Deciphering the factors underlying both long-term patterns of diversity and taxonomic turnover rates (i.e., extinction, and origination) has been one of Paleobiology's major foci for the past three decades. The importance of documenting these components is that they will expand our ability to interpret and model the evolutionary processes underlying those trends, highlight the evolutionary impact of historical events, and contribute to the formulation of robust predictions about the future of global diversity in response to the current anthropologically driven environmental changes. Accordingly, the first part of this study examines the possible occurrence of global marine evolutionary environmental controls into …

Plant Species Richness And Species Area Relationships In A Florida Sandhill, Monica Ruth Downer

USF Tampa Graduate Theses and Dissertations

Pine sandhill are integral pyrogenic communities in the southeastern United States. Though once widespread, habitat destruction, fire suppression and fragmentation have reduced the population to nearly 3%. It is important to learn as much as possible about these unique areas in order to implement best management practices to conserve and restore the existing populations of these communities.

Fire is central to the maintenance of pine sandhill communities and two conceptual hypothesis regarding burn frequency have come to light in maintaining the unique species composition and richness of these areas. The first is the Intermediate Disturbance Hypothesis which suggests that intermediate …

Assessing The Link Between Coastal Development And The Quality Of Fish Habitat In Mangrove Tidal Tributaries, Justin Micheal Krebs

USF Tampa Graduate Theses and Dissertations

To assess the potential influence of coastal development on the quality of estuarine habitat for nekton, we characterized land use and the intensity of land development surrounding small tidal tributaries of Tampa Bay. Based on this characterization, we classified tributaries as undeveloped, industrial, urban or man-made (i.e., mosquito-control ditches). Over one-third (37%) of tributaries were determined to be heavily developed, while fewer than one-third (28%) remain relatively undeveloped. We then examined the nekton community from eleven tributaries in watersheds representing the defined land-use classes. Whereas mean nekton density and species richness were both independent of land use, nekton-community structure differed …

Use Of Adventitious Roots For The Determination Of Hydroperiod In Isolated Wetlands, Michael Joseph Reyes

USF Tampa Graduate Theses and Dissertations

Abstract

Accurate measurement of the hydroperiod in isolated wetlands currently relies upon the installation and frequent monitoring of devices such as piezometers and staff gauges. Observations of biological indicators of the hydroperiod may be able to supplement data collected from these devices and could potentially replace them as a means of accurately determining this hydrologic interval. The study objective was to determine whether adventitious root formation and maturation on buttonbush (Cephalanthus occidentalis) could be used as a viable indicator of the hydroperiod in isolated wetlands. Buttonbush seedlings were flooded in a controlled environment over a three month period in the …

Consequences Of Kleptoplasty On The Distribution, Ecology, And Behavior Of The Sacoglossan Sea Slug, Elysia Clarki, Michael Louis Middlebrooks

USF Tampa Graduate Theses and Dissertations

The sacoglossan sea slug Elysia clarki is able to photosynthesize for three to four months using chloroplasts sequestered from its algal food sources. Furthermore, the slug is able to store multiple chloroplasts from different algal species within the same cell. This research, consisting of several related studies, explores the role that provision of organic nutrients via photosynthesis plays in the biology of the slug. The first chapter demonstrates that, under conditions of starvation, photosynthetic activity in E. clarki remains fully functional for one month after which it then declines. During the first month of starvation the slug exhibits similar feeding …

Ontogeny And Littoral Structure Of Lakes Created On Phosphate Mined Lands Of Central Florida, Chrysoula Mitraki

USF Tampa Graduate Theses and Dissertations

Created lakes are an end product of phosphate mining in Florida. Beginning in 1975, Florida reclamation rules set criteria for phosphate created lakes aiming to approximate the structure of natural lakes, and emphasizing extensive littoral zones with both emergent and submersed vegetation.

Lake development relative to lake age and design were examined for 22 phosphate lakes representing a 40-year age trajectory, utilizing water quality and benthic invertebrate communities from littoral and deep-water locations (Chapter 1). The relative importance of morphometry and lake age in the development of littoral plant communities was examined using multiple vegetation surveys throughout the year, in …

Modification Of Trophic Links Between An Omnivore And Macroinfaunal Prey From Sandy Beaches Of Differing Physical Regimes, Kristina Joan Morrow

USF Tampa Graduate Theses and Dissertations

Sandy beach ecosystems have been studied worldwide; however, ecological data are sparse for the extensive barrier islands of Florida. Accordingly, I investigated the feeding patterns of the ghost crab (Ocypode quadrata), a dominant omnivore inhabiting beaches along the Floridian coast. Density data was collected for ghost crabs and swash macroinfaunal prey. In addition, I utilized stable isotopes in conjunction with the mixing models IsoSource and SIAR to characterize diets of ghost crabs across three barrier islands in spring and summer 2011. Results showed that ghost crabs at Cayo Costa feed primarily on swash macroinfauna, while those from Anclote Key shifted …

Comparative Developmental Transcriptomics Of Echinoderms, Roy Vaughn

USF Tampa Graduate Theses and Dissertations

The gastrula stage represents the point in development at which the three primary germ layers diverge. At this point the gene regulatory networks that specify the germ layers are established and the genes that define the differentiated states of the tissues have begun to be activated. These networks have been well characterized in sea urchins, but not in other echinoderms. Embryos of the brittle star Ophiocoma wendtii share a number of developmental features with sea urchin embryos, including the ingression of mesenchyme cells that give rise to an embryonic skeleton. Notable differences are that no micromeres are formed during cleavage …

Variability In Hydrology And Ecosystem Properties And Their Role In Regulating Soil Organic Matter Stability In Wetlands Of West-Central Florida, Sharon Jean Feit

USF Tampa Graduate Theses and Dissertations

Soil organic matter (SOM) provides many ecosystem services that are necessary for continued ecosystem function. The accumulation of SOM in an ecosystem is a function of its persistence time which can range from days to thousands of years. Ecosystem properties including dominant vegetation type, soil texture, and soil moisture in various habitats can regulate the persistence time of SOM.

Wetlands, because of their associated ecosystem properties, promote SOM accumulation, but little has been done to determine the ecosystem properties that regulate its persistence over time. In west-central Florida, urbanization and increased water demands have suppressed water tables in isolated wetland …

Stable Isotope Analysis Of Busycon Sinistrum To Determine Fort Walton-Period Seasonality At St. Joseph Bay, Northwest Florida, Ryan Michael Harke

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Recent archaeological investigations indicate that coastal Fort Walton cultures in the St. Joseph Bay region of northwest Florida emphasized marine and estuarine foraging. These late prehistoric (A.D. 1000-1500) peoples collected fish, shellfish, and other aquatic resources. At the Richardson's Hammock site (8Gu10), radiocarbon-dated to about A.D. 1300, as at dozens of other shell middens around this salty bay, large gastropods were a major subsistence component. This adaptation is in sharp contrast with that of contemporaneous inland Fort Walton societies, who relied on maize agriculture. It is unknown whether coastal groups represent separate hunter-gatherer-fisher populations or seasonal migrations by inland …

Assessment Of Diver Impact During The Spiny Lobster Sport Season, Florida Keys, Usa, Mark Lewis Hartman

USF Tampa Graduate Theses and Dissertations

The Spiny Lobster (Panulirus argus) fishery in Florida is closed during the spawning season (March-July) except for a two-day recreational `miniseason' for sport divers in July, several days prior to the opening of the commercial fishing season. In Monroe County, recreational fishers, who possess a valid Saltwater Fishing License with crawfish stamp, are allowed to harvest six lobsters per day, each with a minimum carapace length of 76.2 mm (3.0 inches). During these two days, approximately 50,000 people attempt to catch lobster, and the number of boats visiting the reef has been estimated to be up to 900 times higher …

No Honor Among Snails: Conspecific Competition Leads To Incomplete Drill Holes In The Naticid Gastropod Neverita Delessertiana (R Cluz), Jack A. Hutchings

USF Tampa Graduate Theses and Dissertations

The fossil record of drilling predation has been widely used to study predator-prey interactions and their relative importance on long-term evolutionary processes. Incomplete drill holes have been interpreted as indicators of failed attacks due to well-defended prey. However, this interpretation is based on pair-wise interactions between one predator and one prey, a condition commonly compromised in nature. The hypothesis that interference among drilling predators leads to an increase in the relative frequency of incomplete drill holes was tested in the laboratory using the naticid Neverita delessertiana (R cluz) and a common prey, the bivalve Chione elevata (Say). The experiment consisted …

Dolphin Sound Production And Distribution On The West Florida Shelf, Peter Simard

USF Tampa Graduate Theses and Dissertations

This dissertation is an investigation of dolphin sound production and distribution off west central Florida. Although a wealth of information exists on the production of common sounds (whistles, echolocation) made by captive, trained dolphins, far less is known about free-ranging dolphin sound production and of unusual sounds. In addition, while inshore dolphin populations or communities are the subjects of research projects in many locations, dolphins in offshore waters are less commonly studied. The objectives of this dissertation were to contribute information on free-ranging dolphin sounds and continental shelf dolphin distribution.

While echolocation has been rigorously studied in captive, trained dolphins, …