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Ecology Of Earthworms In Riparian Habitats, Rebecca Annette Pinder

Legacy Theses & Dissertations (2009 - 2024)

Research on earthworm ecology in North America has shifted from a focus on agricultural systems to investigations of their impacts on forested ecosystems. Many of the earthworms (family Lumbricidae, Megascolecidae, and Sparganophilidae) found so far appear to be groups of exotic species, many recently arrived from Eurasia. My preliminary research established their presence along forested headwater stream banks, previously assumed to be earthworm-free zones. These riparian areas are integral landscape elements that influence many downstream processes. This dissertation is the first to examine four aspects of earthworm ecology in riparian zones: species composition and distributions; community structure of earthworm assemblages; …

Developmental Adaptation Hypothesis : Aerobic Capacity, Submaximal Arterial Saturation And Pulmonary Volumes In Peruvian Quechua Natives, Melisa Kiyamu Tsuchiya

Legacy Theses & Dissertations (2009 - 2024)

The Quechua populations have inhabited the Andes for hundreds of generations. The ability to thrive in this hostile environment, leading an active and healthy life has generated research questions about the special phenotype of Andean highlanders compared to their sea-level counterparts, such as their higher pulmonary volumes and their outstanding work capacity in spite of the challenge of oxygen transport and delivery in hypoxia. In high altitude natives, there have been two main explanations for the origins of the aforementioned traits: genetic adaptation through natural selection and developmental adaptation through the exposure to hypoxia during growth.

Modeling The Ecological Niche Of The Nigeria-Cameroon Chimpanzee Under Climate Change, Paul Ryan Sesink Clee

Legacy Theses & Dissertations (2009 - 2024)

Ecological niche theory states that a set of environmental conditions exists that a species relies upon in order to survive and reproduce. Collectively, these variables define a species' niche, which includes a species' dispersal abilities and its range. Ecological niche modeling predicts the distributions of species by using information from environmental variables across geographic space, making it a valuable tool for studying how environment affects population dynamics. With accurate species presence data and geospatial information that describe its known habitat, ENMs can effectively map a species' realized niche across geographical space, and for closely related taxa, be used to understand …

What To Eat Now? Shifts In Polar Bear Diet During The Ice-Free Season In Western Hudson Bay, Linda J. Gormezano, Robert F. Rockwell

Publications and Research

Under current climate trends, spring ice breakup in Hudson Bay is advancing rapidly, leaving polar bears (Ursus maritimus) less time to hunt seals during the spring when they accumulate the majority of their annual fat reserves. For this reason, foods that polar bears consume during the ice-free season may become increasingly important in alleviating nutritional stress from lost seal hunting opportunities. Defining how the terrestrial diet might have changed since the onset of rapid climate change is an important step in understanding how polar bears may be reacting to climate change. We characterized the current terrestrial diet of polar bears …

Heifer Calving Date Positively Influences Calf Weaning Weights Through Six Parturitions, R. A. Cushman, L. H. Kill, Richard N. Funston, E. M. Mousel, G. A. Perry

West Central Research and Extension Center, North Platte

Longevity and lifetime productivity are important factors influencing profitability for the cowcalf producer. Heifers that conceive earlier in the breeding season will calve earlier in the calving season and have a longer interval to rebreeding. Calves born earlier in the calving season will also be older and heavier at weaning. Longevity data were collected on 2,195 heifers from producers in South Dakota Integrated Resource Management groups. Longevity and weaning weight data were collected on 16,549 individual heifers at the U.S. Meat Animal Research Center (USMARC). Data were limited to heifers that conceived during their first breeding season. Heifers were grouped …

International Polar Year (Ipy) Back To The Future (Btf): Changes In Arctic Ecosystem Structure Over Decadal Times Scales, Sandra Villarreal

Open Access Theses & Dissertations

Arctic vegetation communities are responding to climate warming through shifts in species composition and diversity but most observations have been made over relatively short time frames, and/or in association with experimental manipulations. Because vegetation plays a key role in regulating ecosystem productivity, nutrient cycling, surface energy budgets, and trophic interactions in the Arctic, there is a need to better understand shifts in tundra vegetation communities over decadal time scales. Understanding these shifts and their impact on ecosystem structure and function in the Arctic has important implications for predicting the future state of both the Arctic and the Earth System. Long …

Does Pitcher Plant Morphology Affect Spider Residency?, Marc A. Milne, Deborah A. Waller

Biological Sciences Faculty Publications

Spiders are often found as residents in association with Sarracenia purpurea ( Purple Pitcher Plant). Many spiders choose web locations based on environmental cues such as vegetation structure and composition, prey density, temperature, and humidity. To determine if spiders use cues from the Purple Pitcher Plant to build their webs, we conducted a field study using variants of the plant that separated various morphological features: nectar, pigment, and the presence of prey. There was no difference in spider residency across all treatments and no difference in male/female or mature/immature residency. Linyphiids were the most common residents, possibly due to pitcher …

The Population Dynamics Of Two Rodents In Two Coastal Marshes In Virginia, Robert K. Rose, John A. March

Virginia Journal of Science

The communities of small mammals were evaluated for 13 months with capture-mark-recapture methods in two Spartina-Juncus marshes of the Atlantic coast in Northampton County, Virginia. Small mammals were trapped for three days each month using live traps placed on floats on two study grids. Two rodents were numerically dominant (~90% of small mammals) there: marsh rice rat, Oryzomys palustris, and meadow vole, Microtus pennsylvanicus. Monthly estimates of population density were greater for rice rats (peak: 45/ha) than for those of meadow voles (peak: 30/ha). Survival rates were generally low, especially for rice rats, indicating highly vagile populations. Both …

The Small Mammals Of Two Dune Communities In Southeastern Virginia, Robert K. Rose, Justin L. Sweitzer

Virginia Journal of Science

Small mammals were surveyed using live and pitfall traps between the primary and secondary dunes at two locations on the shores of the Chesapeake Bay near the Atlantic Ocean: Little Creek Amphibious Base in Norfolk and Joint Expeditionary Base Fort Story in Virginia Beach, Virginia. Captures were dominated by house mice (Mus musculus) in interdunal habitats with sparse grass, whereas white-footed mice (Peromyscus leucopus) were found primarily in shrubby live-oak thickets on the tops of dunes. Hispid cotton rats (Sigmodon hispidus) were present only at Fort Story, and then only in patches of dense …

The Causes And Consequences Of Individual Variation In Parental Care Behavior, Daniel P. Wetzel

Theses and Dissertations--Biology

Behavioral traits can be remarkably flexible depending on the conditions in which they are expressed, yet, in spite of this flexibility, persistent differences between individuals appear to limit the potential expression of behaviors. For example, despite evidence that parents provide variable amounts of parental care in response to changing environmental conditions, they also differ in the overall level of care they provide. I used a behavioral reaction norm approach to study individual variation in parental care behavior in free-living house sparrows (Passer domesticus). I investigated the nature of this variation by studying the relationship between different forms of …

Selective Utilization Of Microhabitats By Web-Building Spiders, Kelton D. Welch

Theses and Dissertations--Entomology

Natural enemies are members of complex ecological communities, and their ability to contribute to the biological control of pest organisms is strongly influenced by a convoluted network of ecological interactions with many other organisms within these communities. Researchers must develop an understanding of the mechanisms that shape trophic webs to predict and promote top-down effects of predators. The behavior of predators can have a strong influence on their potential as biological control agents.

Web-building spiders are a useful example organism for the study of natural enemy behavior because of the experimentally tractable nature of their foraging behavior. Specifically, patterns in …

Genetic Diversity Of North American Captive-Born Gorillas (Gorilla Gorilla Gorilla), Noah D. Simmons, Ronald S. Wagner, Joseph G. Lorenz

All Faculty Scholarship for the College of the Sciences

Western lowland gorillas (Gorilla gorilla gorilla) are designated as critically endangered and wild populations are dramatically declining as a result of habitat destruction, fragmentation, diseases (e.g., Ebola) and the illegal bushmeat trade. As wild populations continue to decline, the genetic management of the North American captive western lowland gorilla population will be an important component of the long‐term conservation of the species. We genotyped 26 individuals from the North American captive gorilla collection at 11 autosomal microsatellite loci in order to compare levels of genetic diversity to wild populations, investigate genetic signatures of a population bottleneck and identify …

Microsatellite Analysis Of Trophy Largemouth Bass From Arkansas Reservoirs, K. A. Lamothe, Ronald L. Johnson

Journal of the Arkansas Academy of Science

The Arkansas Game and Fish Commission (AGFC) has introduced Florida largemouth bass (FLMB; Micropterus salmoides floridanus) to water bodies historically containing the northern largemouth bass (NLMB; Micropterus salmoides salmoides) subspecies since the late 1970s in an attempt to produce a trophy LMB fishery. Since 2006, the AGFC has been biannually sampling reservoirs stocked with FLMB to determine levels of admixture. Here, total sampling efforts between 2006 and 2011 have been combined, and LMB heavier than 2,268 g (5 lb) were analyzed in an effort to investigate distribution of bass by their genetic composition designated as trophy LMB by the AGFC. …

Threats And Knowledge Gaps For Ecosystem Services Provided By Kelp Forests: A Northeast Atlantic Perspective, Dan A. Smale, Michael T. Burrows, Philippa J. Moore, Nessa O'Connor, Stephen J. Hawkins

Research outputs 2013

Kelp forests along temperate and polar coastlines represent some of most diverse and productive habitats on the Earth. Here, we synthesize information from >60 years of research on the structure and functioning of kelp forest habitats in European waters, with particular emphasis on the coasts of UK and Ireland, which represents an important biogeographic transition zone that is subjected to multiple threats and stressors. We collated existing data on kelp distribution and abundance and reanalyzed these data to describe the structure of kelp forests along a spatial gradient spanning more than 10° of latitude. We then examined ecological goods and …

Variation In Population Densities Of The Florida Scrub Lizard (Sceloporus Woodi) Between Managed Sand Pine Scrub And Longleaf Pine Stands In The Ocala National Forest, Matthew D. Kaunert

College of Graduate Studies: Theses & Dissertations

Population-level response to habitat fragmentation is central to applied species management and conservation. Managed landscapes are often subject to increased fragmentation and, consequently, may force once connected populations to function as metapopulations. Studies investigating metapopulations occurring over patchy, managed landscapes are of increasing importance as fragmentation is a known cause of biodiversity loss. In June-September 2012, populations of the rare, endemic Florida scrub lizard (Sceloporus woodi) were sampled across the Ocala National Forest (ONF) to compare abundance and density across two management types. In the ONF, sand-pine scrub is clearcut and rollerchopped whereas longleaf pine is managed via …

Evaluating The Utility Of Beaver Reintroduction Programs For Enhancing Habitat For Rainbow Trout And Steelhead, Jonathan Rodger Hegna

All Master's Theses

Beaver reintroduction programs are increasingly being viewed as a way to enhance salmonid habitat and production. However, the actual effectiveness of using beavers as a habitat enhancement tool for ESA listed steelhead Oncorhynchus mykiss populations is unknown. We examined the type of habitat, at both the microhabitat and mesohabitat levels, preferred by steelhead in three small streams in the upper Yakima Basin, WA through standard snorkel surveys and habitat measurements. Our results suggest that steelhead in small streams strongly prefer (relative to availability) microhabitats that have deeper water(> 30 cm), slow stream velocities(< 0 .05 mis), and complex cover types. Habitat partitioning among the size-classes (small< 50 mm, medium 50-90 mm, large> 90 mm total length, TL) principally operated …

Spatial And Temporal Patterns In Ungulate-Ecosystem Interactions, Bryan D. Murray

Dissertations, Master's Theses and Master's Reports - Open

Ungulates are important components of a variety of ecosystems worldwide. This dissertation integrates aspects of ungulate and forest ecology to increase our understanding of how they work together in ways that are of interest to natural resource managers, educators, and those who are simply curious about nature. Although animal ecology and ecosystem ecology are often studied separately, one of the general goals of this dissertation is to examine how they interact across spatial and temporal scales. Forest ecosystems are heterogeneous across a range of scales. Spatial and temporal habitat use patterns of forest ungulates tend to be congregated in patches …

Topographic Home Range Of Large Mammals: Is Planimetric Home Range Still A Viable Method?, W. David Walter, Justin W. Fischer, Teresa J. Fink, Scott E. Hygnstrom, Jonathan A. Jenks, Kurt C. Vercauteren

Natural Resource Management Faculty Publications

Topography influences movement trajectories, quality of forages used, and behavioral response of large herbivores to anthropogenic disturbances, but research is lacking on the influence of terrain complexity on size of home range. Size of home range usually is based on planimetric area and therefore rarely accounts for the true surface area traversed by an animal. We conducted radiotelemetry on bighorn sheep (Ovis canadensis), Rocky Mountain elk (Cervus elaphus), mule deer (Odocoileus hemionus), and white-tailed deer (O. virginianus) equipped with VHF collars at three sites from 2002 to 2006 to document size of home range in areas that ranged from 400 …

Insight Into Human Brain Evolution Through Phylogenetic Analysis And Comparative Genomics, Amy Marie Boddy

Wayne State University Dissertations

As a species, humans are often considered to be unique among mammals, with respect to their large brain size and enhanced cognitive abilities. Humans are the most encephalized mammals, with a brain that is six times larger than expected relative to body mass. Presumably, it is this high degree of encephalization that underlies our advanced cognitive abilities, including the skills needed for complex language and culture. Understanding how large brains evolved can shed light on what makes the human brain unique and introduce possible mechanism for human specific neurodegenerative diseases. This study takes a both a phenotypic and molecular approach …

Winter Behavior And Ecology Of Eastern Bluebirds (Sialia Sialis): Home Ranges, Habitat Use, And Effect Of Weather On Foraging Behavior, Todd J. Weinkam

Online Theses and Dissertations

Eastern bluebirds (Sialia sialis) are widespread across eastern North America, but populations appear to be susceptible to extreme winter weather. Declines in population following cold winters in states like Kentucky suggest the need to better understand winter-specific habitat requirements and behavioral responses to inclement weather. My objectives were to 1) describe the size and habitat composition of the home ranges of wintering bluebirds, and 2) examine the effects of weather (i.e., temperature, wind speed, and snow presence) on habitat occupancy, group size, and foraging behavior. My study was conducted at the Blue Grass Army Depot in Madison County, …

Habitat Associations Of Stream-Dwelling Salamanders At Multiple Spatial Scales In Central Kentucky Headwaters., John Mark Yeiser

Online Theses and Dissertations

Headwater stream systems are productive habitats that are often at risk of human perturbation, and it is crucial that ecologists understand natural patterns and processes within these ecosystems. Using a multi-scale approach, I investigated factors influencing habitat associations of Ambystoma barbouri (streamside salamander) and Eurycea cirrigera (southern two-lined salamander) in a relatively undisturbed stream network in central Kentucky. I used likelihood ratio G-tests to identify associations between species and mesohabitat types (i.e., runs, riffles, and pools). I used second order Akaike's Information Criterion (AICc) model selection to predict patterns of presence and abundance throughout headwater reaches. Fine-scale abiotic …

Effects Of Thermal Acclimation On The Critical Thermal Maxima Of The Tropical Cockroaches: Blaptica Dubia, Eublaberus Posticus And Blaberus Discoidalis (Blaberidae), Lauren Michelle Goode

Online Theses and Dissertations

The Critical Thermal Maxima (CTMax) is a measure of upper thermal tolerance. The physiological response upon reaching CTMax is similar across taxa, making CTMax useful in comparative studies. The CTMax defines the ecological lethal temperature of an organism and has been used to predict the effects of global climate change. CTMax was determined for adults and first instar nymphs of three species of tropical cockroaches: Blaptica dubia, Eublaberus posticus, and Blaberus discoidalis. Adult cockroaches were acclimated to temperatures of 10°C, 15°C, 20°C, 25°C, 31°C and 37°C for a period of seven days. Blaptica dubia was the only species to survive …

The Subtle Intracapsular Survival Of The Fittest: Maternal Investment, Sibling Conflict, Or Environmental Effects?, Kathryn E. Smith, Sven Thatje

Ocean Engineering and Marine Sciences Faculty Publications

Developmental resource partitioning and the consequent offspring size variations are of fundamental importance for marine invertebrates, in both an ecological and evolutionary context. Typically, differences are attributed to maternal investment and the environmental factors determining this; additional variables, such as environmental factors affecting development, are rarely discussed. During intracapsular development, for example, sibling conflict has the potential to affect resource partitioning. Here, we investigate encapsulated development in the marine gastropod Buccinum undatum. We examine the effects of maternal investment and temperature on intracapsular resource partitioning in this species. Reproductive output was positively influenced by maternal investment, but additionally, temperature and …

Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Historically, the Kentucky Inner Bluegrass blue ash-oak savanna-woodland was the primary ecosystem of the Inner Bluegrass Region (IBR) of Kentucky. After European settlement, the majority (>99%) of Bluegrass savanna was converted to agricultural and urban land uses. Currently remnant savanna tree species are failing to recruit. Therefore, a long-term restoration ecology project researching competition and disturbance on seedling establishment, survival, and growth has been established at Griffith Woods (the largest remaining savanna in Kentucky) in Harrison Co., KY. Fourteen native hardwood tree species (a total of 6,168 seedlings) have been experimentally planted. Light, soil, surrounding vegetation, and herbivory, factors …

The Lives Of Others: Social Rationality In Animals, Jeffrey R. Stevens, Andrew J. King

Jeffrey Stevens Publications

Darwin (1871) boldly claimed that humans and other animals differ very little in their cognition; a statement that has raised the ire of many scientists (Bolhuis & Wynne, 2009; Penn, Holyoak, & Povinelli, 2008). Rather than stating this continuity as a fact, we will explore the similarities and differences between humans and animals in the social rationality of their decision making. We find this a fruitful exercise because it can profit researchers of both humans and animals. Our purpose here is to provide an evolutionary background of social rationality: Why do animals attend to the lives of others? To this …

Worms, Nematoda, Scott Lyell Gardner

Scott L. Gardner Publications

Nematodes are the most speciose phylum of metazoa on earth. Not only do they occur in huge numbers as parasites of all known animal groups, but also they are found in the soils, as parasites of plants, and in large numbers in the most extreme environments, from the Antarctic dry valleys to the benthos of the ocean. They are extremely variable in their morphological characteristics, with each group showing morphological adapta­tions to the environment that they inhabit. Soil-dwelling forms are extremely small; many marine species have long and complex setae; and parasitic species man­ifest amazingly great reproductive potential and large …

Refining Thresholds In Coupled Fire–Vegetation Models To Improve Management Of Encroaching Woody Plants In Grasslands, Dirac L. Twidwell Jr, Samuel D. Fuhlendorf, Charles A. Taylor Jr, William E. Rogers

Department of Agronomy and Horticulture: Faculty Publications

1. Restoration priorities are typically established without quantitative information on how to overcome the thresholds that preclude successful restoration of desirable ecosystem properties and services. We seek to demonstrate that quantifying ecological thresholds and incorporating them into management-oriented frameworks provide a more comprehensive perspective on how the threshold concept can be applied to achieve restoration goals.

2. As an example, restoration actions have been largely unsuccessful when based on prevailing ecological knowledge of fire-based thresholds in nonresprouting Juniperus woodland. We build on previous threshold-based research and link well-established models from applied fire physics with a widely applied ecological positive feedback …

Changing Room Cues Reduces The Effects Of Proactive Interference In Clark’S Nutcrackers, Nucifraga Columbiana, Jody L. Lewis, Alan C. Kamil, Kate E. Webbink

Avian Cognition Papers

To determine what factors are important for minimizing interference effects in spatial memory, Clark’s Nutcrackers, Nucifraga columbiana were tested for their spatial memory for two serial lists of locations per day. In this experiment two unique landmark sets were either different between List 1 and List 2 or the same. We found that Nutcrackers were most susceptible to interference when the landmark sets were the same. This study suggests that repeatedly testing animal memory in the same room, with the same cues, can hamper recall due to interference.

Differences In Relative Hippocampus Volume And Number Of Hippocampus Neurons Among Five Corvid Species, Kristy L. Gould, Karl E. Gilbertson, Andrew J. Hrvol, Joseph C. Nelson, Abigail L. Seyfer, Rose M. Brantner, Alan C. Kamil

Avian Cognition Papers

The relative size of the avian hippocampus (Hp) has been shown to be related to spatial memory and food storing in two avian families, the parids and corvids. Basil et al. [Brain Behav Evol 1996;47: 156-164] examined North American food-storing birds in the corvid family and found that Clark’s nutcrackers had a larger relative Hp than pinyon jays and Western scrub jays. These results correlated with the nutcracker’s better performance on most spatial memory tasks and their strong reliance on stored food in the wild. However, Pravosudov and de Kort [Brain Behav Evol 67 (2006), 1-9] raised questions …

Antelope Mating Strategies Facilitate Invasion Of Grasslands By A Woody Weed, Shivani Jadeja, Soumya Prasad, Suhel Quader, Kavita Isvaran

School of Biological Sciences: Faculty Publications

Intra and interspecific variation in frugivore behaviour can have important consequences for seed dispersal outcomes. However, most information comes from among-species comparisons, and within-species variation is relatively poorly understood. We examined how large intraspecific differences in the behaviour of a native disperser, blackbuck antelope Antilope cervicapra, influence dispersal of a woody invasive, Prosopis juliflora, in a grassland ecosystem. Blackbuck disperse P. juliflora seeds through their dung. In lekking blackbuck populations, males defend clustered or dispersed mating territories. Territorial male movement is restricted, and within their territories males defecate on dung-piles. In contrast, mixed-sex herds range over large areas …