Life Sciences Commons^™

Exploring The Consistency Of Flow Regimes Within And Among Ecoregions Of The Southeastern United States, Frank Paul Braun Iv

Electronic Theses and Dissertations

Human manipulation of river systems has long been a known contributor to the loss of freshwater biodiversity. By accounting for environmental causes of hydrologic variation among rivers, we can better understand how ecoregion mediates flow regimes and forecast species that may be at risk. Presumably, natural variation associated with ecoregion boundaries exerts strong influence on flow regimes, and may mediate relationships between other features (e.g., land use, dam operations) and hydrology. However, such between-ecoregion variation is poorly investigated, particularly at fine spatial and temporal scales. I characterized 10 hydrologic metrics, representing the five key dimensions of the flow regime (magnitude, …

Neonate Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) Relative Abundance And Body Condition In Two South Carolina Estuaries Varying In Urbanization, Rileigh E. Hawk

Electronic Theses and Dissertations

Urbanization near estuaries has been shown to affect the growth and survival of juvenile sharks using the system as a nursery. North Inlet and Murrells Inlet, South Carolina, are similarly-sized, tidally-dominated, bar-built estuaries with extensive Sporobolus-lined tidal creeks but differ in degree of human impact. Previously, Murrells Inlet was shown to have a lower abundance and diversity of large sharks than North Inlet and Atlantic Sharpnose Sharks (Rhizoprionodon terraenovae) were shown to use North Inlet as a primary nursery. To examine potential differences in neonate shark abundance and growth between a developed estuary, Murrells Inlet, and a protected estuary, North …

Evaluating Translocation Strategies For Box Turtles In Urbanizing Landscapes, Elizabeth D. Hays

Biological Sciences Undergraduate Honors Theses

Urbanization of landscapes, resulting in habitat degradation, loss, and fragmentation, is a significant contributor to the global decline of reptile biodiversity. Although translocation is a common management strategy for wildlife populations subject to urbanization, the efficacy of reptile translocation studies, including those of box turtles (Terrapene spp.), is highly variable. Hard-release translocation of box turtles has often proven ineffective due to homing attempts and rapid post-translocation movements. Some studies have presented soft-release as a possible method for mitigation of the negative effects of hard-release, yet those studies have also produced mixed results. Therefore, I radiotracked 18 translocated Terrapene carolina …

Immunological Tradeoffs And The Impacts Of Urbanization On The Reproductive Ecology And Physiology Of The Side-Blotched Lizard (Uta Stansburiana), Emily E. Virgin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investing resources into reproduction can limit energy available to other competing demands, such as fighting off an infection; yet, both processes are necessary for organisms to survive and pass on their genes to the next generation. These strategies often follow patterns associated with lifespan, such that shorter-lived animals are more likely to invest more resources into reproduction over survival, and vice versa in long-lived animals. However, environmental change caused by urbanization can disrupt these relationships, and the within- and transgenerational costs of urbanization on females and offspring are unknown. I address these uncertainties in three research chapters to better understand …

Loggerhead Shrike Detectability And Occurrence In Coastal South Carolina Urban Areas, Michelle Krauser

Electronic Theses and Dissertations

Grassland birds, such as the loggerhead shrike (Lanius ludovicianus), are threatened by extensive land-use change, including urbanization. Loggerhead shrikes have been declining since the early 1900s and are rare or extirpated in portions of their former range. Obtaining reliable population estimates of loggerhead shrikes is important to identify demographic trends and ensure conservation decisions are based on an accurate assessment of their current status. Imperfect detection, or the inability to detect every shrike during a survey, can result in biased population estimates. Estimating detection probability is labor-intensive and requires assumptions that are difficult to satisfy in most field studies. Understanding …

Urban Habitats Impact The Song And Reproductive Success Of A Migratory Bird, The Gray Catbird (Dumetella Carolinensis), Sasha Ewing

Masters Theses, 2020-current

Urban environments are relatively recent on an evolutionary timescale, and, as such, they create novel selection pressures that may influence fitness and mate choice. Many ecologically significant factors change with increasing levels of urbanization, such as increasing anthropogenic noise, increasing impervious surface, and decreasing forest cover. There is growing empirical evidence that anthropogenic noise affects features of birdsong and, separately, that avian nesting success varies across an urban gradient, but rarely do studies examine both – a necessary step to elucidate the evolutionary potential of these novel pressures. I investigated song features, body morphometrics, and reproductive success in male gray …

Is Immediate Flexibility Present In A Vocal Mimic, The Gray Catbird (Dumetella Carolinensis), Across An Urban Gradient?, Shannon K. Eppert

Masters Theses, 2020-current

Increasing urbanization has increased anthropogenic noise levels near developed areas. Urban noise is high amplitude and low-frequency, and these frequencies can overlap with the signals animals use to communicate, including bird songs. Many urban birds sing higher minimum frequencies in urban areas, which avoids some masking by noise, but the mechanism behind this difference is not well understood. Immediate flexibility is the ability to alter song in real-time in the presence of sudden noise, allowing for avoidance of masking and better signal transmission. I investigated if male catbirds increased signal transmission in the presence of anthropogenic versus high-frequency noise playback …

The Effects Of Urbanization On The Avian Gut Microbiome, Mae Berlow

Doctoral Dissertations

The gut microbiome influences and is influenced by the host, and can affect the host organism by contributing to health, development and immunity. Similarly, the host can influence this community; it’s makeup can vary with host species, locality, diet, social stressors, and environmental stressors. Some of these environmental stressors have arisen due to human-induced rapid environmental change, like urbanization. The physiology and behaviors of organisms that are able to persist in urban environments are often different from their non-urban congeners. Nutrition, development, and immunity—all of which are affected by the gut microbiome—are important factors that can determine survival in urban …

The Effects Of Urbanization On Insect Morphology: A Meta-Analysis, Evann L. Bailey

Honors Theses

Urbanization has been shown to create a rapid change in the environment as you move from rural areas to urban areas. It can create a multitude of effects on the environment. Some examples include, land disturbance, pollution, increasing temperatures and a disturbance in vegetation and biodiversity. Insects are useful organisms that provide maintenance and upkeep for ecosystem functioning. The rapid development of urbanization and how it is changing the environment may impact insect morphology. Measuring morphological change in organisms have been used successfully as indicators of environmental and ecological disturbance. Changes that take place in an insect’s morphology may indicate …

Comparing Semi-Urban And Forest Populations Of The Jalisco Mud Turtle (Kinosternon Chimalhuaca), Jose Garrido

All Master's Theses

Mud turtles (family Kinosternidae) are primarily threatened by climate change, overexploitation, and land development. To survive in increasingly urbanized and arid regions, mud turtles often inhabit man-made water sources such as cattle troughs and irrigation ditches. These bodies of water are critical in urban habitat where they may offer some of the last remaining refugia; however, the effect of these conditions on population structure is poorly understood. The Jalisco mud turtle (Kinosternon chimalhuaca) was described in 1997 from a small range south of Puerto Vallarta, Mexico. Since its description, critical ecological research has remained largely nonexistent, hindering …

Improving Understanding Of Forest Communities And Biodiversity With Multi-Dimensional Landscape Gradients, Ben J. Padilla

Doctoral Dissertations

This dissertation was motivated by a desire to understand the effects of habitat degradation and urbanization on a single species in a single study system in western Massachusetts, the red-backed salamander (Plethodon cinereus), but along the way unexpected conceptual and methodological hurdles caused the work to grow into a multi-species, multi-region, and multi-scale endeavor. As I designed my dissertation research and began considering approaches to quantifying heterogeneity and human influence in my study landscape, I recognized inconsistencies in methods used to define and quantify landscape metrics, particularly in urban systems. To investigate further, I conducted a critical review …

Determining The Impacts Of Urbanization On Song Structure And Its Function In Territorial Defense For Gray Catbirds (Dumetella Carolinensis), Morgan L. Rhodes

Masters Theses, 2020-current

In urbanized habitats, animals are faced with novel selection pressures such as differences in community structure and increased urban noise. Urban noise pollution can negatively impact songbirds as low-frequency noise often masks portions of birds’ mating signal and reduces signal transmission. Previous research has demonstrated that songs of birds in more urban habitats have structural differences that enhance signal transmission when noise is present. These studies have focused on species that deliver short, stereotyped songs with limited repertoires. Gray catbirds (Dumetella carolinensis, family: Mimidae) sing long bouts containing imitated, improvised, and invented song elements, and therefore may have …

Conospermum Undulatum: Insights Into Population Genetics And Pollination Ecology Of A Threatened Species, Nicola Delnevo

Theses: Doctorates and Masters

Fragmentation of natural vegetation is currently one of the largest threats to biodiversity. Within the southwest Australia global biodiversity hotspot, the Swan Coastal Plain was historically cleared for agriculture and forestry and is now experiencing extensive land clearing for urbanisation. The wavy-leaved smokebush Conospermum undulatum is a rare species endemic to the Swan Coastal Plain, and its future persistence is threatened by urban expansion.

Throughout this research, I investigated the pollination ecology of this species and found a specific association between C. undulatum and native bees for pollination. I also demonstrated that C. undulatum has evolved pollen with resistance to …

Long-Term Trends Of Stream Fish Community Assemblages In Southern Missouri With Contemporary Land Use Impacts, Stephanie Marie Sickler

MSU Graduate Theses

Stream fish communities in the Ozarks are structured via a number of different mechanisms, including basin, stream size, and human land use. The purpose of this study was to understand the structuring mechanisms of stream fish communities in southern Missouri. I compiled 48 years of historical fish collections performed by the Ichthyology class at Missouri State University consisting of 140 sites. I resampled 45 of these sites in summer of 2016. First, I tested whether communities are different between basins and stream size. Next, I tested associations of land use at three spatial scales to local fish communities. Last, I …

Wildlife Use Of Vernal Pools In An Urbanizing Landscape With A Focus On Population Vitality Of Vernal Pool-Breeding Amphibians, Carly Jasmine Eakin Phd

Electronic Theses and Dissertations

Vernal pools in the northeastern United States provide essential habitat for pool-breeding amphibians and provide resources for other forest-dwelling wildlife. These pools and pool-breeding amphibians in particular are threatened by land conversion associated with urbanization and urban-associated factors. The responses of these amphibians and of birds and mammals using vernal pools to intermediate levels of urban development are largely unknown. I used field observations and lab experiments to study the amphibians, birds, and mammals associated with vernal pools along an urban development gradient in greater Bangor, Maine.

In Chapter 1, I examined bird and mammal use and assemblage composition at …

Urbanization Impacts On Land Snail Community Composition, Mackenzie N. Hodges

Masters Theses

Urbanization has tremendous impacts on most native species. Urban ecosystems are becoming increasingly prevalent, while urban ecology is a relatively underdeveloped field. This is especially true for terrestrial mollusks, which are a surprisingly understudied organism. Due to their low mobility and dispersal potential, land snails are valuable indicators of ecosystem disturbance. For this study, land snails were collected in 54 city parks along an urban gradient to understand influences of urbanization on snail communities. Sampled parks include small extensively landscaped downtown parks, neighborhood and community parks, district parks, and large nature parks, each with variable vegetation, soil characteristics, disturbance regimes, …

Nestmate Recognition In Odorous House Ants (Tapinoma Sessile): Effects Of Social Plasticity, Urbanization, And Laboratory Maintenance, Timothy J. Luttermoser

Open Access Theses

Odorous house ants (Tapinoma sessile) are a widespread North American ant species and common nuisance pest. In addition to their pest status, odorous house ants are of interest as a model system for understanding the factors that lead to variable queen number and nesting strategy across ants, as well as possible insight into common traits of exotic invasive (or “tramp”) ant species. While T. sessile is native to North America, in urban environments it forms large supercolonies with many queens and nest sites connected by trails, similar to a variety of exotic invasive ants, most of which are …

Host Densities And Parasitism Rates In A Forest Defoliator Across A Rural-Urban Landscape, Abigail J. Nelson

Theses and Dissertations

Fall cankerworm (FCW) outbreaks have recently increased in frequency and intensity in the mid-Atlantic region of the United States, especially around cities of Charlotte, NC and Richmond, VA. This study evaluated the effects of two landscape features associated with urbanization, impervious surface and forest cover, on population patterns of FCW and its parasitoids across eastern Virginia. Forest cover was positively related to parasitism rates while impervious surface was positively related to FCW abundance, suggesting that FCW outbreaks may be amplified in urban areas. FCW abundance declined over the two-year period of this study, but parasitism rate increased at most sites. …

A New Adaptive Landscape: Urbanization As A Strong Evolutionary Force, Lauren Christie Breza

Masters Theses

Urbanization is rapidly increasing as human population growth steadily grows, but there is little consensus of the ecological consequence of this population shift and almost no information of the evolutionary consequences for local biodiversity. Nearly two-thirds of the world’s population will live in city centers by 2050 with profound impacts on landscapes that can act as important agents of selection. This study aims to identify 1) the net effect of urbanization on species richness, 2) how phylogenetic diversity varies between urban and rural sites, and 3) the strength of urbanization as a selection pressure. First, a meta-analysis was conducted in …

Emergent Insect And Neotropical Migratory Bird Interactions And Responses To Habitat, Hydrology, And Progressive Urbanization In The Tampa Bay Region, Nathaniel Lee Goddard

USF Tampa Graduate Theses and Dissertations

The growing human population threatens the many of the earth’s biological systems. In the last 600 years extinction rates risen from 1 extinction per million species per year (E/MSY) in the 1400’s to 50 E/MSY today. During this time period 1.5% of all known birds have gone extinct, because they could not adapt quickly enough to human mediated changes. The goal of this dissertation was to determine how urbanization and anthropogenic services needed to support urban areas impact cypress dome wetland aquatic insect and migratory bird populations that depend on them. In Central Florida cypress dome hydroperiods are driven by …

The Effects Of Urbanization On Tick Parasitism Rates In Birds Of Southeastern Virginia, Erin Leigh Heller

Biological Sciences Theses & Dissertations

The coastal region of southeastern Virginia is one of the largest urban areas along one of North America’s migratory flyways. Because hundreds of avian species use this flyway, understanding factors affecting birds and their health is of paramount concern. Within this region, 14 species of ticks have been documented, all of which may serve as vectors of mammal (including human) pathogens. By sampling birds at sites of varying levels of urbanization within the coastal southeastern urban matrix, I studied the relationship between ticks and their avian hosts, and how this relationship varies seasonally. Mistnets were set-up at five permanent sites …

Productivity And Habitat Features Of Swainson's Hawks (Buteo Swainsoni) Nesting In Suburban And Agricultural Areas Of Southwest Idaho, Steven Edward Alsup

Boise State University Theses and Dissertations

I compared nesting success and productivity of Swainson’s Hawks nesting in suburban and agricultural areas in southwest Idaho to assess the effects of land use change on Swainson’s Hawk reproduction. I also evaluated habitat parameters and land use patterns around nesting areas to determine if nest site, habitat, and/or landscape features were related to reproductive success in Swainson’s Hawks. I recorded habitat characteristics, nest tree characteristics, distances to four habitat features, and disturbance types, as well as land use patterns within a 1500m radius around nest trees to assess any differences in nest site characteristics, habitat features, and/or landscape features …

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 …