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Articles 1 - 18 of 18
Full-Text Articles in Life Sciences
Which Vole Is Which: Dna-Based Species Identification For Wisconsin’S Three Microtus Species, Madeline Noel Opie
Which Vole Is Which: Dna-Based Species Identification For Wisconsin’S Three Microtus Species, Madeline Noel Opie
Theses and Dissertations
Accurate species identification is necessary to implement conservation strategies in the wild. When traditional morphology-based species identification is challenging due to phenotypic plasticity, overlapping characteristics, or the species are otherwise cryptic, DNA-based species identification may be more suitable. Of the three species of Microtus in Wisconsin, two are listed as threatened at the state level. Both M. ochrogaster and M. pinetorum have stable population levels at the national level but are along the northern edge of their ranges in Wisconsin. Small and vulnerable populations of M. ochrogaster and M. pinetorum are limited to isolated patches in the southwestern portion of …
Determining The Impact Of Post-Harvest Water Management On Chironomid Abundance, Agrochemical Biomass And Potential Trophic Biomagnification, Mason Thomas
Theses and Dissertations
Agriculture has diminished shorebirds’ natural habitat in the Mississippi Alluvial Valley. Remaining natural stopover sites are supplemented with agricultural fields during the fall and winter. This study evaluates the impact of 4 different post-harvest water management strategies on shorebird food abundance and potential agrochemical biomagnification. Chironomid samples estimated abundance, biomass, and chironomid agrochemical concentration in each field. A risk assessment of agrochemical biomagnification to shorebirds was made across all treatments. Of treatments represented on all study sites, winter treatment had greatest chironomid abundance and biomass. Models indicated that days since flood initiation, start date, and temperature are significant predictors of …
Effects Of Soil Management Practices On Water Infiltration And Maize Yield To Improve Mississippi River Valley Alluvial Aquifer Sustainability, Jacob Rix
Theses and Dissertations
Surface sealing and hardpans in loam soils are problematic in the Mid-South U.S. because of intense tillage. Two experiments quantified the effects of soil management practices on infiltration and maize yield in loam soils. The first study measured the impacts of in-row subsoiling frequency × furrow irrigation frequency. In-row subsoiling significantly improved the infiltration of irrigation but not the infiltration of precipitation. In-row subsoiling with low irrigation frequency is optimal to achieve profitable maize yields while encouraging groundwater conservation. In the second study, six soil management treatments were imposed. For single-ring infiltrometer tests, infiltration rates were different between the two …
Molecular Evolution And Biogeography Of The New World Eptesicus Bats, Xueling Yi
Molecular Evolution And Biogeography Of The New World Eptesicus Bats, Xueling Yi
Theses and Dissertations
Molecular evolution refers to a broad field of studies ranging from microevolution (e.g., population genetics) to macroevolution (e.g., phylogeny), including the bridging field of phylogeography. In natural populations, molecular studies are also combined with biogeography that links biological diversity with geographic distributions to provide a comprehensive understanding of evolutionary processes. The field of molecular evolution has been largely advanced from early exploratory descriptions to statistical tests on biological hypotheses and integrative analyses using sophisticated modeling. However, studies of molecular evolution still face some unresolved questions and challenges, especially in non-model systems. For example, the application of new technology has largely …
Status, Distribution, And Conservation Of The Black-Spotted Newt (Notophthalmus Meridionalis) In South Texas, Padraic S. Robinson
Status, Distribution, And Conservation Of The Black-Spotted Newt (Notophthalmus Meridionalis) In South Texas, Padraic S. Robinson
Theses and Dissertations
The Black-spotted Newt (Notophthalmus meridionalis) is a chronically understudied species, with much information on the natural history, ecology, and distribution of this species poorly known. Previous studies using traditional methodologies have had limited success detecting N. meridionalis. A novel eDNA assay was designed and implemented with the goal of better understanding N. meridionalis distribution in south Texas. Primers were designed to amplify N. meridionalis DNA and tested against DNA from sympatric amphibians. This assay combined with traditional methods was implemented at 62 sites throughout south Texas, and N. meridionalis was detected at eight localities. At each site …
Body States Of Asian Elephants Within And Around Protected Areas In The Salakpra Wildlife Sanctuary, Kanchanaburi, Thailand, Caitlyn Thai
Body States Of Asian Elephants Within And Around Protected Areas In The Salakpra Wildlife Sanctuary, Kanchanaburi, Thailand, Caitlyn Thai
Theses and Dissertations
Researchers are becoming increasingly aware that studying a species’ landscape of fear or, more broadly, their emotional states, can better inform cognitive questions about how animals navigate their environments. Vigilance behaviors are one way to determine how certain species perceive and respond to risky situations. Due to rapid environmental change, large animals such as elephants are experiencing risky encounters with humans more often than ever before. This study aims to investigate Asian elephants’ expressions of body states and how they might regulate their behavior based on perceived environmental risk or change. Specifically, we investigated the behavioral responses of Asian elephants …
Assessment Of Wild Ring-Tailed Lemur (Lemur Catta) Populations In Southwestern Madagascar With Implications For The Illegal Pet Trade, Samantha D. Calkins
Assessment Of Wild Ring-Tailed Lemur (Lemur Catta) Populations In Southwestern Madagascar With Implications For The Illegal Pet Trade, Samantha D. Calkins
Theses and Dissertations
Accurate population estimates are critical to inform conservation management of species. Incomplete sampling can lead to population underestimates and lacking conservation efforts. Population surveys are important for assessing human and animal welfare to allow for targeted conservation action. Recent ring-tailed lemur (Lemur catta) surveys have led researchers to conclude that L. catta populations are crashing. This has generated much attention and alarm, but may also be based on incomplete information. To better understand population dynamics, more thorough sampling is needed. Here, we survey five such sites to reassess the presence and abundance of L. catta in these locations. …
Observation Of Visitors At A Chimpanzee (Pan Troglodytes Schweinfurthii) Ecotourism Site Reveals Opportunity For Multiple Modes Of Pathogen Transmission, Darcey Glasser
Theses and Dissertations
Chimpanzee (Pan troglodytes) tracking is a popular ecotourism activity across Sub-Saharan Africa, offering visitors a personal wildlife experience. However, chimpanzee ecotourism may increase the risk of disease transmission between chimpanzees and people. This study assessed how tourist behaviors might facilitate cross-species disease transmission in Kibale National Park, Uganda.
Ontogeny Of Similarity And Disparity In Length-At-Age Of Coral Reef Fishes In The Family Acanthuridae Between Marine Protected And Fished Areas, Mathias Tjarko Cramer
Ontogeny Of Similarity And Disparity In Length-At-Age Of Coral Reef Fishes In The Family Acanthuridae Between Marine Protected And Fished Areas, Mathias Tjarko Cramer
Theses and Dissertations
Drastic reductions in the harvestable biomass of exploited fish populations on coral reefs and other marine coastal ecosystems have been hypothesized to be a consequence of astronomical and unrelenting fishing pressures, particularly in the coastal small-scale and sustenance fisheries of the world. It has recently been proposed that the causal relationship between fishing pressure and fish biomass is rooted in the negative effects of size-selective fishing mortality, which consequently instigates directional shifts in phenotype (i.e., fishing induced evolution). To mitigate the effects of unsustainable fishing pressures, parcels of traditional fishing grounds have been designated as Marine Protected Areas (MPAs). To …
Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal
Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal
Theses and Dissertations
The objective of this investigation was to examine the foraging patterns and population density of the Buff-bellied Hummingbird (Amazilia yucatanensis ) in Hidalgo County, TX. Previous studies showed that hummingbirds use flowers displaying traditional bird pollination (ornithophilous) characteristics: reddish coloration, tubular corolla, and extended anthers. Observation sessions noted type and frequency of flowering species utilized for nectar, characteristics, and number of individuals seen in each area. Amazilia yucatanensis showed higher use of ornithophilous flowers. Significant results found: f-ratio 5.45 > p-value (0.05) 3.24. Two highly utilized species showed the expected 20–40% sucrose content expected in ornithophilous flowers. Population density per …
Conspecific Attraction In A Low-Density Population Of A Threatened Songbird, Daniel James Albrecht-Mallinger
Conspecific Attraction In A Low-Density Population Of A Threatened Songbird, Daniel James Albrecht-Mallinger
Theses and Dissertations
Many organisms use both vegetation structure and social cues in selecting habitats. Many species of songbirds use the presence of breeding conspecifics as a social cue and sign of habitat quality, and can be induced to settle in unoccupied habitats by artificially broadcasting breeding song, a process referred to as “conspecific attraction”. In our study, we tested response to conspecific attraction a low-density population of the threatened Golden-winged Warbler (Vermivora chrysoptera) in Highland County, VA. Response to broadcast song was observed, with a modest increase in mean male abundance at survey points within 250 meters of treatments, and mean abundance …
Personhood And Cloning: Modern Applications And Ethics Of Stem Cell And Cloning Technology, Sariah Cottrell Mccarrey
Personhood And Cloning: Modern Applications And Ethics Of Stem Cell And Cloning Technology, Sariah Cottrell Mccarrey
Theses and Dissertations
Within many communities and religions, including the LDS community, there is some controversy surrounding the use of stem cells – particularly embryonic stem cells (ESC). Much of this controversy arises from confusion and misconceptions about what stem cells actually are, where they come from , and when life begins. The theology of the Church of Jesus Christ of Latter-day Saints has interesting implications for the last of these considerations, and it becomes less a question of “when does life begin” and more an exploration of “when does personhood begin” or “when does the spirit enter the body.” With no official …
Diversity And Abundance Of The Dark Kangaroo Mouse, Microdipodops Megacephalus, In Communities Of Nocturnal Granivorous Rodents In Western North America, Ashley Sagers Haug
Diversity And Abundance Of The Dark Kangaroo Mouse, Microdipodops Megacephalus, In Communities Of Nocturnal Granivorous Rodents In Western North America, Ashley Sagers Haug
Theses and Dissertations
The dark kangaroo mouse, Microdipodops megacephalus, is a sensitive species in the Great Basin Desert. This thesis explores the structure of desert rodent communities of the Great Basin to better understand M. megacephalus' place in the community and the conditions that promote large and stable populations. To determine community structure, I used nestedness analysis to evaluate 99 communities of nocturnal granivorous rodents. I found that the community structure was non-random, indicating the existence of assembly rules and ecological constraints. I also found that M. megacephalus was the second most vulnerable species in the community. To explore the correlation …
Pygmy Rabbit (Brachylagus Idahoensis) Habitat Use, Activity Patterns And Conservation In Relationship To Habitat Treatments, Janet E. Lee
Pygmy Rabbit (Brachylagus Idahoensis) Habitat Use, Activity Patterns And Conservation In Relationship To Habitat Treatments, Janet E. Lee
Theses and Dissertations
This study examined activity patterns and habitat use of pygmy rabbits (Brachylagus idahoensis) in mechanically treated and untreated areas in south-central Utah 2005-2008. We monitored fecal pellet plots in continuous sagebrush habitat as well as along treatment edges to record deposition and leporid presence over timed periods. Pygmy rabbit use of big sagebrush was higher than black-tailed jackrabbits (Lepus californicus) and mountain cottontail rabbits (Sylvilagus nuttallii ) (P< 0.01) relative to treated areas (P <0.01). We also compared pygmy rabbit use of areas with continuous sagebrush to residual sagebrush in a sample of mechanically treated areas. Our results suggest a treatment effect with higher (P <0.01) average counts of pygmy rabbit pellets in areas with continuous sagebrush compared to sagebrush strips and islands within treated areas. Before the big sagebrush biotype inhabited by pygmy rabbits is treated to reduce the occurrence and dominance of big sagebrush, we recommend managers consider two options. The first is no treatment, thus preserving, as is, the critical habitat of the pygmy rabbit and other sympatric big sagebrush obligate species of wildlife. The second option cautiously introduces the first prescription of habitat treatment ever recommended in relationship to the pygmy rabbit. This prescription includes recommended widths of the treated areas, seed mixes, widths of the preserved intact big sagebrush habitat for pygmy rabbits as well as suggested grazing systems for domestic livestock. Activity patterns of pygmy rabbits at their burrow were documented through the use of remote cameras. Photographs were analyzed for temporal and seasonal patterns of activity. Our results suggested that time of day was important in the activity level of pygmy rabbits while season was not. Pygmy rabbits were active during all time periods of the day but the greatest levels of activity occurred at night. Numerous other wildlife species were recorded by our remote cameras including other species of leporids, birds, rodents, reptiles and terrestrial predators.
Genetic Considerations For The Conservation And Management Of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) In Yellowstone National Park, David J. Janetski
Genetic Considerations For The Conservation And Management Of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) In Yellowstone National Park, David J. Janetski
Theses and Dissertations
A key component to conservation is an accurate understanding of genetic subdivision within a species. Despite their ecological and economic importance, relatively little is understood about the genetic structuring of Yellowstone cutthroat trout in Yellowstone National Park. Here, we use traditional (Fst, Rst, Nm, and AMOVA) and modern (Bayesian assignment tests, coalescent theory, and nested clade analysis) analytical approaches to describe the population genetic subdivision of cutthroat trout spawning populations in Yellowstone Lake and to identify genetically distinct population segments throughout Yellowstone National Park. Evidence for restricted gene flow between spawning populations within Yellowstone Lake was detected using nested clade …
Ecological Investigations Of Chukars In Western Utah, Randy T. Larsen
Ecological Investigations Of Chukars In Western Utah, Randy T. Larsen
Theses and Dissertations
This thesis presents three separate manuscripts in chapter format dealing with the ecology of Chukars (Alectoris chukar) in western North America. All three manuscripts have been formatted for publication in professional journals. Chapter one confirms discovery of ingested lead pellets in Chukars across a broad region of western Utah including all four western counties sampled. Prevalence rates were 1.9% (n=105) for crops and 10.7% (n=75) of gizzards showing no evidence of penetration wounds. Ingestion is likely related to grit size preferences that are consistent with common shot sizes. The second chapter describes watering patterns and water-site selection of Chukars. Chukars …
Phylogeny And Biogeography Of Ice Crawlers (Insecta: Grylloblattodea): Evidence From Six Molecular Loci, Karl J. Jarvis
Phylogeny And Biogeography Of Ice Crawlers (Insecta: Grylloblattodea): Evidence From Six Molecular Loci, Karl J. Jarvis
Theses and Dissertations
Ice crawlers (Insecta: Grylloblattodea) are rarely encountered insects that consist of five genera representing 26 species from North America and Asia. Asian grylloblattids are the most diverse, but North American ice crawlers (genus Grylloblatta) are known for their adaptation to cold conditions. Phylogenetic relationships among grylloblattid species and genera are not known. Late Pleistocene glaciations had a major effect on the current Grylloblatta distribution, because their specific habitat requirements restrict them to small geographical areas. Six genes were sampled in 37 individuals for 18S rRNA, 28S rRNA, histone 3, 12S rRNA, 16S rRNA, and cytochrome oxidase II (COII) from 27 …
Density Effects On Growth, Survival And Diet Of June Sucker (Chasmistes Liorus): A Component Allee Effect In An Endangered Species., David Barrett Gonzalez
Density Effects On Growth, Survival And Diet Of June Sucker (Chasmistes Liorus): A Component Allee Effect In An Endangered Species., David Barrett Gonzalez
Theses and Dissertations
Density-dependence is considered one of the most important regulators of population growth, and it has been documented across a wide variety of species. Typically, population growth rate and components thereof decline with increasing density (i.e., negative density-dependence); however, in species that exhibit high population densities and social behavior, positive density-dependence (i.e., Allee effect) may occur at low density. June sucker, a federally endangered lake sucker endemic to Utah Lake, Utah, USA, occurred historically at high density, and it exhibits coordinated feeding behavior. These characteristics indicate a potential for the existence of an Allee effect at current low population densities. To …