Life Sciences Commons^™

Estimating Density And Residency Of Bottlenose Dolphins (Tursiops Truncatus) In Three Estuarine Sites In South Carolina, Jessica Nicole Conway

Electronic Theses and Dissertations

Of the three estuarine bottlenose dolphin stocks in South Carolina, two are considered data insufficient, with no minimum population estimate or assigned potential biological removal value. Additionally, the Northern Georgia Southern South Carolina Estuarine System (NGSSCES) stock’s boundaries are based on sighting data that do not extend to the full area encompassed by the boundary lines. In areas where stock boundaries are not clearly defined and data is insufficient for traditional methods of estimating abundance, density may provide insight into local distributions and serve as a proxy for actual abundance. Photo-identification surveys were conducted in three sites, representative of the …

Nonspreading Solutions In Integro-Difference Models With Allee And Overcompensation Effects., Garrett Luther Otto

Electronic Theses and Dissertations

Previous work in Integro-Difference models have generally considered Allee effects and over-compensation separately, and have either focused on bounded domain problems or asymptotic spreading results. Some recent results by Sullivan et al. (2017 PNAS 114(19), 5053-5058) combining Allee and over-compensation in an Integro-Difference framework have shown chaotic fluctuating spreading speeds. In this thesis, using a tractable parameterized growth function, we analytically demonstrate that when Allee and over-compensation are present solutions which persist but essentially remain in a compact domain exist. We investigate the stability of these solutions numerically. We also numerically demonstrate the existence of such solutions for more general …

Spatially Explicit Model Of Areas Between Suitable Black Bear Habitat In East Texas And Black Bear Populations In Louisiana, Arkansas, And Oklahoma, Caitlin M. Glymph, Christopher Comer, Daniel Scognamillo, Daniel Unger, Yanli Zhang

Electronic Theses and Dissertations

Although black bears (Ursus americanus, Ursus americanus luteolus) were once found throughout the south-central United States, unregulated harvest and habitat loss resulted in severe range retractions and by the beginning of the twentieth century populations in Oklahoma, Louisiana, Texas and Arkansas were nearing extirpation. In response to these losses, translocation programs were initiated in Arkansas (1958-1968 & 2000-2006) and Louisiana (1964-1967 & 2001-2009). These programs successfully restored bears to portions of Louisiana and Arkansas, and, as populations in Arkansas began dispersing, to Oklahoma. In contrast, east Texas remains unoccupied despite the existence of suitable habitat in the region.

To facilitate …

American Woodcock Migration Ecology At An Important Stopover, Cape May, New Jersey, Brian B. Allen

Electronic Theses and Dissertations

Migration poses risks and energetic demands to individuals that may be greater than those experienced during non-migratory periods. Most migratory birds require stopover sites to rest and recuperate energy spent during migratory flights, and stopover locations can alleviate risks and provide supplemental energy en route to the animal’s end destination. An individual’s stopover duration is contingent first on energy acquisition that is constrained by resource availability, and secondarily on environmental conditions such as weather that may facilitate or constrain continued migration. From 2010 to 2013 I conducted a radio-telemetry study of a short-distance migrant, the American Woodcock (Scolopax minor), on …

Lobster In A Changing Gulf Of Maine: Investigating The Temporal Impact On Molting And The Fishing Fleet, Kevin W. Staples

Electronic Theses and Dissertations

We investigated the phenological and fisheries dynamics surrounding the spring molt of American lobster (Homarus americanus, Milne Edwards 1847) in the Gulf of Maine. We created a time series from Maine Department of Marine Resources Lobster Sea Sampling data using logistic models to estimate the timing and duration of the spring molt for eastern, central, and western regions of the Maine coast. These estimates revealed substantial inter-annual variability in the timing of the spring molt for all regions and that 2012 was indeed anomalously early relative to other years. Each region experienced significantly different molt timing for any given …

Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis

Electronic Theses and Dissertations

Understanding population dynamics and how species interact with their environment are important components for conservation and management. Ruffed grouse (Bonasa umbellus) are a widely distributed and common game bird in North America and are a considered an important economic and cultural icon in Maine. Although they are a well-studied species, there has been little research focused on ruffed grouse population dynamics and habitat relationships in Maine. My thesis aims to improve this knowledge gap by focusing on research related to survival and harvest of ruffed grouse, as well as male ruffed grouse resource selection at breeding display sites. Ruffed grouse …

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver

Electronic Theses and Dissertations

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase.

Historically, …

Ecological Informatics: An Agent Based Model On Coexistence Dynamics, Shiva Thapa

Electronic Theses and Dissertations

The coexistence of species is probably one of the most interesting and complex phenomenon in nature. We constructed an agent based model to study the coexistence dynamics of prey - predator populations by varying productivity levels of producers in fragmented and connected habitats along with different levels of quality of predators. Our results indicated that productivity levels of producers in fragmented and connected habitats along with levels of predator quality are significantly responsible for overall predator - prey population size and survivorship. In the absence of predation, competition between identical prey populations is more probable in connected habitats than in …

Enemy Exacerbation: Effects Of Predator Stress On Sulfate Lethality In Freshwater Amphipods (Gammarus Minus), Trevor Chapman

Electronic Theses and Dissertations

Predator cues can influence how aquatic organisms respond to anthropogenic contaminants. This study examined the effects of predator cues on behavior, metabolic rate, and sulfate (as Na₂SO₄) toxicity in amphipods (Gammarus minus). Predator cues included alarm cue (macerated conspecifics) and kairomone from mosquitofish (Gambusia affinis). Amphipods decreased activity and increased time in refuge when exposed to alarm cue, and increased time in refuge when exposed to kairomone. While median lethal concentrations (96-h LC₅₀) were not influenced by predator cues, analysis of dose response curves indicated that kairomone exposure increased amphipod …

Breeding Ecology And Habitat Use Of Unisexual Salamanders And Their Sperm-Hosts, Blue-Spotted Salamanders (Ambystoma Laterale), Kristine Hoffmann

Electronic Theses and Dissertations

Unsexual Salamanders within the Blue-Spotted Salamander Complex carry combinations of ambystomatid genomes (those of Blue-Spotted Salamanders, Ambystoma laterale, and Jefferson Salamanders, A. jeffersonianum in Maine). They are nearly all female, breed in wetlands, and use sperm of related species to reproduce. Little is known about their ecology to guide the conservation of this unique lineage. I examined breeding site occupancy, demographics, orientation, and terrestrial habitat selection of Unisexual Salamanders in comparison to Blue-Spotted Salamanders and other amphibians. I compared statistical tests of orientation to determine which was most appropriate for pitfall data.

Unisexual Salamander occupancy at breeding sites was positively …

Population Ecology Of Colonially Breeding Seabirds: How Intrinsic Processes, Mediating Influences, And Individual Heterogeneity Affect Population Vital Rates, Aly Mcknight

Electronic Theses and Dissertations

Seabirds have great potential to serve as marine indicators. However, before we can interpret seabird trends with confidence, we need a better understanding of the role of intrinsic processes, mediating influences, and lifetime experience in modulating relationships between prey availability and seabird population dynamics.

Intrinsic processes, mediating influences, and seabird productivity. I assessed productivity (chicks per breeding attempt) at Black-legged Kittiwake (Rissa tridactyla) colonies in Prince William Sound, AK and managed Common Tern (Sterna hirundo) colonies in the Gulf of Maine. Both systems showed evidence of intrinsic control; factors mediating access to prey were also important.

Mediating influences, individual heterogeneity, …

Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer

Electronic Theses and Dissertations

Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …

The Biogeographic Origins And Trophic Ecology Of Maine’S Island Red-Backed Salamanders (Plethodon Cinereus), Nikko-Ideen Shaidani

Electronic Theses and Dissertations

Island populations of terrestrial species have an increased potential, compared to mainland populations, to adapt and diverge, as these populations often are isolated with respect to gene flow from other populations and may be subjected to novel pressures. Indeed, extended isolation of individuals can elicit dramatic changes within populations and is recognized as a common driver of speciation. It is for these reasons that island populations are often a priority for conservation. Plethodontid salamanders are among the most terrestrial of Maine’s amphibians and are not tolerant of prolonged exposure to seawater, and yet, they are found on a number of …

Effects Of Dam Removal On Assemblage Composition And The Interactions Of Fishes In The Penobscot River, Maine, Jonathan Watson

Electronic Theses and Dissertations

Dams and their impoundments disrupt river habitat connectivity to the detriment of migratory fishes. Removal of dams improves riverine connectivity and lotic habitat which benefits these fishes along with resident fluvial specialist species. Restoration efforts on the Penobscot River (Maine, USA) are among the largest recently completed in the United States, and include the removal of the two lower-most dams and improvements to fish passage at several remaining barriers. Here we describe initial and potential future changes to fish communities in the Penobscot River associated with these restoration efforts.

We assessed fish assemblages in the mainstem river and several major …

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …

Cranial Morphological Distinctiveness Between Ursus Arctos And U. Americanus, Benjamin James Hillesheim

Electronic Theses and Dissertations

Despite being separated by millions of years of evolution, black bears (Ursus americanus) and brown bears (Ursus arctos) can be difficult to distinguish based on skeletal and dental material alone. Complicating matters, some Late Pleistocene U. americanus are significantly larger in size than their modern relatives, obscuring the identification of the two bears. In the past, fossil bears have been identified based on differences in dental morphology or size. This study used geometric morphometrics to look at overall differences in cranial shape and used step-wise discriminant analysis to identify specific characters that distinguish cranial morphology between …

Niche Modeling For The Giant Panda, Ailuropoda Melanoleuca, And The Original Panda, Ailurus Fulgens: Habitat Preferences And Evolutionary Consequences, Lauren M. Lyon

Electronic Theses and Dissertations

The well-known symbol for conservation, the giant panda bear, and the original red panda have been forced into remote habitats due to anthropogenic disturbance, making ecological study difficult. Therefore the first known species distribution model was created to predict the most likely areas of occurrence within the known range of these elusive animals. These models were then projected onto North America and evaluated against existing breeding programs. Additionally, the close proximity of the Gray Fossil Site and the discovery of the most complete fossil red panda specimens in the world allowed ecomorphological comparisons between the modern red panda, Ailurus fulgens …

Environmental Factors, Not Plants, Contribute To Functional Diversity Of Soil Bacteria In The Dunes Of Lake Michigan., Andrea Stark Howes

Electronic Theses and Dissertations

Soil bacteria play important roles in nutrient cycling and other ecosystem functions, and many biotic and abiotic factors can influence bacterial functional diversity. The goal of this field study was to examine differences among bacterial communities in sand dunes of Lake Michigan. I used Biolog Ecoplates™ to compare bacteria functional diversity associated with four different plant species: the native dune-building grass Ammophila breviligulata, invasive species Leymus arenarius and Gypsophila paniculata, and native legume Lathyrus japonicus across 13 sites in Michigan, representing a gradient in abiotic factors such as precipitation and temperature. I found no differences in bacterial function associated with …

Intraspecific Differences In Belowground Associations And Seedling Root Morphology For The Biofuel Crop, Panicum Virgatum., Erin Renee Kinnetz

Electronic Theses and Dissertations

The perennial C₄ grass Panicum virgatum (switchgrass) is a promising bioenergy feedstock. Switchgrass is symbiotic with arbuscular mycorrhizal fungi (AMF). I examined 12 varieties of switchgrass grouped into 2 ecotypes (upland, lowland) to see if they differed in AMF abundance and root colonization using the GLBRC Variety Trials experiment. There was higher root colonization of lowland ecotype. A greenhouse experiment evaluated the role of live soil organisms in seedling establishment of 11 varieties. Live soil increased seedling survival, growth and influenced root morphology. Ecotypes differed in root architecture. Lowland developed a higher specific root length (SRL), a trait associated …

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 …

Phenotypic Plasticity Of Native And Invasive Cool-Season Grasses In Response To Frequency Of Moisture Availability, Ming-Yu Stephens

Electronic Theses and Dissertations

Phenotypic plasticity, the ability of an individual to alter its growth in response to environmental conditions, is an attribute that is considered a likely invader attribute, as it provides the opportunity to expand its ecological niche breadth. Adaptive phenotypic plasticity can affect not only the ability to establish in a new environment, but also the ability to outperform the existing vegetation over time. Bromus inermis (smooth brome) and Poa pratensis (Kentucky bluegrass) are invasive species in tall- and mixed-grass prairie ecosystems. The objectives of this two-part study were to quantify the adaptive plasticity of biomass accumulation and tiller production in …

Evaluation Of The Deadwood Bighorn Sheep Herd Translocation, Ty J. Werdel

Electronic Theses and Dissertations

From 2015-2017, we evaluated a newly established bighorn sheep (Ovis canadensis) herd in the Deadwood Region of the Black Hills, South Dakota. Our objectives were to 1a) determine annual survival rates, 1b) determine cause-specific mortality, 1c) estimate population size, 2a) assess genetic diversity, 2b) assess disease prevalence, 3) evaluate movement patterns post-release, 4a) evaluate 3rd-order habitat selection, and 4b) estimate herbaceous biomass at foraging sites post-release of translocated bighorn sheep. In February 2015, we captured and translocated 26 bighorn sheep from the Luscar Mine near Hinton, Alberta, Canada to the Deadwood Region of the Black Hills, South Dakota. Overall annual …

Dna Metabarcoding Reveals Provisioning Of Pollution-Sensitive Aquatic Insects, Resource Partitioning, And Dietary Shifts Among Breeding Neotropical Migratory Songbirds In A Riparian Habitat, Brian K. Trevelline

Electronic Theses and Dissertations

Elucidating the diet of Neotropical migratory birds is essential to our understanding of their ecology and to their long-term conservation. Beyond broad taxonomic or morphological categories, however, the diet of Neotropical migrants is poorly documented. Using the molecular techniques of DNA barcoding and next-generation sequencing, we elucidated the diet of Neotropical migratory songbirds breeding in the riparian zones of headwater Appalachian streams. This approach resulted in a genus- or species-level description of diets that improved the current understanding of how songbirds utilize aquatic prey resources in riparian habitats. Furthermore, our approach revealed that breeding songbirds partition prey resources within a …

Molecular Analysis Of The Mating System Of A Population Of Fantail Darter (Etheostoma Flabellare) In Bates Fork, Greene Co., Pa, Ashley Seitz

Electronic Theses and Dissertations

In May 2013, we examined the mating system of the Fantail Darter, Etheostoma flabellare, from a population inhabiting Bates Fork, a small tributary of the Monongahela River in Greene County, PA. Guarding adult male Fantail Darters excavate an area under a flat rock in moderately flowing rifles. Females select a male or his territory and deposit clusters of eggs on the underside of the nest rock. The guarding male provides all parental care. The locations of 23 nests were mapped over a 139m² stream segment before collecting embryos and attending males for a genetic parentage analysis. DNA was …

Primate Proteomic Composition Of Seminal Plasma And Prostate-Specific Transglutaminase Activity In Relation To Sexual Selection., Amanda M.C. Zielen

Electronic Theses and Dissertations

Humans (Homo sapiens), chimpanzees (Pan troglodytes), and gorillas (Gorilla gorilla) have diverse mating systems with varying levels of sperm competition. Several seminal plasma genes have been claimed to evolve under positive selection, while others are altered or lost. This study aims to identify biologically relevant differences among seminal plasma proteomes of primates in relation to mating systems and previous genomic studies. Seminal plasma from three individuals of each species were run in triplicate in shotgun liquid chromatography – tandem mass spectrometry (LC-MS/MS) and confirmed with Western blots. Over 7,000 peptides were identified across all …

Distribution Changes, Genetic Population Structure, And A Novel Environmental Dna (Edna) Detection Method For Darters (Subgenus Nothonotus) In The Upper Ohio River Watershed, Anthony S. Honick

Electronic Theses and Dissertations

In the upper Ohio River watershed three species of small-bodied benthic fish the Bluebreast Darter, Etheostoma (Nothonotus) camurum (Cope), the Tippecanoe Darter, Etheostoma (Nothonotus) tippecanoe Jordan and Evermann, and the Spotted Darter, Etheostoma (Nothonotus) maculatum Kirtland previously existed in disjunct distributions due to poor water quality and habitat degradation. Signs of recovery indicated that these species were moving from areas of refugia into the deeper mainstem waters of the Allegheny and Ohio rivers and expanding their distributions. To provide information for the proper conservation management of these species this dissertation was divided into three stages: 1) distribution records were updated …

Mountain Lion (Puma Concolor) Population Characteristics And Resource Selection In The North Dakota Badlands, Randy D. Johnson

Electronic Theses and Dissertations

Mountain lions (Puma concolor) have significant ecological impacts on the ecosystems they inhabit, leading to both biological and social ramifications. Yet, due to the relatively recent natural recolonization by mountain lions of the Little Missouri Badlands Region of western North Dakota, detailed data regarding many aspects of this population have been lacking. Therefore, we studied mountain lions occupying the Badlands Region to improve our understanding of mountain lion population ecology, resource selection, and occurrence in North Dakota. Our objectives were to: 1) improve the accuracy of home range size, subadult movement, and survival estimates of mountain lions in …

Quantifying And Simulating Fine-Scale Spatial Patterns In Plant Populations, Darin Schulte

Electronic Theses and Dissertations

Plant ecology as a discipline has increasingly acknowledged the importance of fine-scale spatial patterns in developing our understanding of community/population dynamics. These spatial patterns are largely determined by direct and indirect interactions between plants and their immediate neighbors. Such interactions thus play an important role in the structure and function of plant communities. Study of these types of local interactions has greatly benefitted from simulation based approaches. one such simulation method, agent-based modeling, has increasingly been identified as a useful tool for simulating these fine-scale interactions, and for investigating theoretical descriptions of underlying processes. Similarly, statistical techniques aimed at quantifying …

Competition And Community Interactions Of Two Generalist Herbivores, Elizabeth Ellen Barnes

Electronic Theses and Dissertations

Competition can have far-reaching consequences for the fitness and distribution of many organisms. In herbivorous insects, competition mediated by a third organism is more common than direct competition and has a strong effect on insect communities; yet most research on indirect competition among herbivores focuses on dietary specialists, and those studies that do include generalists tend to rear them on agricultural crops. My project examines species interactions at three levels: intraspecific competition (within species), interspecific competition (between species), and ecosystem engineering effects at the community level. I studied competition and community interactions of two temporally-separated species of herbivorous insects, western …

Risk, Reward, And The Role Of Habitat Selection On Community Dynamics In Temporary Ponds, Matthew Robert Pintar

Electronic Theses and Dissertations

The processes that generate patterns of species diversity within and among habitat patches are a fundamental topic of interest in ecology. Traditionally, there was a focus on post-colonization effects such as predation, however, pre-colonization processes, such as habitat selection, are equally important determinants of community structure. In freshwater systems, the lethal effects of dominant predators (particularly fish) are well established, while the transition from permanent to temporary ponds is a defining characteristic. This transition produces distinct communities characterized by organisms with complex life cycles and plastic developmental strategies. This means that many organisms occupying habitat patches arrive there by the …