Biology Commons^™

Drivers Of Decadal Vegetation Change In Northern Alaska, Jacob Allen Harris

Masters Theses

The Arctic is experiencing rapid climate change. This research documents vegetation change near Atqasuk and Utqiaġvik, Alaska. At each location, 30 plots distributed in a matrix across the landscape, were sampled annually from 2010 to 2019 using a point frame. For every encounter we recorded the height and classified it into eight broad functional groups (deciduous shrubs, evergreen shrubs, forbs, graminoids, bryophytes, lichens, litter and standing dead vegetation); for vascular plants we also identified the species. We found a consistent increase in plant stature and cover over time which was dramatic at Atqasuk. Graminoid cover and height increased at both …

Spatial Use By Mammals Within Two State Parks In The Ozarks National Scenic Riverways, Benjamin Aaron Smith

MSU Graduate Theses

A mammalian species inventory with comparisons between sampled sites was conducted via multiple methodologies to document presence of mammals at two Missouri state parks within the Ozark National Scenic Riverways. Camera traps, small mammal traps, acoustic detectors, and mist nets were used to detect species at the parks, and species similarity indices and occupancy analyses were used to discern use of space. A mammalian inventory was compiled for each area of inquiry. Greater diversity was found at the park with more variable habitat types. Bat activity was more in the park with a known hibernaculum, though species specific activity differed …

Global Conservation Status Of Croaker And Drum (Family: Sciaenidae) And Role Of The Maw Trade, Claire E. Gorman

Biological Sciences Theses & Dissertations

Understanding threats and drivers of extinction risk is critical to conserving marine biodiversity. Although marine bony fishes are some of the most diverse and abundant vertebrates in the world, overexploitation is the major threat to these taxa. Species in the family Sciaenidae are important marine resources in many parts of the world, supporting small- and large-scale fisheries for consumption and the international maw (dried swimbladder) trade. Sciaenids exhibit a diverse array of life history characteristics, such as high fecundity, large body size, formation of spawning aggregations, and longevity. Some characteristics increase their susceptibility to anthropogenic stressors. Despite being ecologically and …

A Survey Of Leaf Venation In New Caledonian Syzygium (Myrtaceae), Jiawei Xu Montojo

Electronic Theses & Dissertations

New Caledonia is a globally recognized biodiversity ‘hotspot’ characterized by a rich flora and a large number of endemic species. Syzygium Gaertn., the largest genus of woody plants in the world, is common in New Caledonia with approximately 70 species. A comparative survey of leaf morphology and architectural traits among 27 species of New Caledonian Syzygium was conducted, focusing on leaf venation patterns. Separate and detailed descriptions of leaf morphology and leaf venation characters are provided for the species. In addition to morphological differences, this study found differences at the species level among characters such as the number of intramarginal …

Quantifying Structure And Variation In Complex Phylogenetic Data, Genevieve Geraldine Mount

LSU Doctoral Dissertations

Identifying the source and structure of variation in nature is crucial to understanding fundamental aspects of evolution. Despite a recent plethora of genetic and morphological data, many interesting questions about the relationships between different groups remain unresolved. My dissertation evaluates three approaches for identifying and quantifying the variation within phylogenetic datasets. Characterizing variation within datasets and across analytical methods gives insight into biologically interesting characters, unusual evolutionary processes, and areas for model improvement.

Network-based community detection approaches offer a powerful tool to describe variation in phylogenetic signal across the genome (i.e., gene tree variation). In Chapter 2, I investigate the …

Spatio-Temporal Dynamics Of Fungal Communities And Their Effects On Plants, Kel Cook

Biology ETDs

Fungi perform several critical functions in the environment. Spatiotemporal distributions of fungal communities will mediate when and where these functions happen and how they vary across the landscape. I first explored tropical tree canopy fungal community variation at small spatial scales and documented near total turnover of fungi across sub-meter distances and among adjacent substrates. The second chapter analyzed fungal turnover over the course of three years, where community stability was driven primarily by abundant fungi. In the third chapter, I tested effects of the environment, including host plant and habitat, on canopy fungal communities and found only small effects, …

Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes

Biology ETDs

Few studies have examined inoculum potential of ectomycorrhizal fungi (EMF) in the absence of plant hosts, yet persistence of these fungi may be paramount to resilience of Pinus edulis and other mycorrhizal plant species. We conducted a study in which seven sites were selected in northwestern New Mexico with known dates of P. edulis extirpation and a lack of regeneration. Age classes included: two sites extirpated 10-20 years ago, two extirpated 55-65 years ago, two extirpated 500+ years ago, and one extirpated 11,000+ years ago. At each site, two plots were paired: an extirpated plot and the nearest live adult …

Distributions And Abundances Of The Red Tide Dinoflagellate Alexandrium Catenella In The Eastern Gulf Of Maine And Bay Of Fundy In Relation To Diatoms In June, July And August Of 2019, Kimberly Lina D'Adamo

Electronic Theses and Dissertations

A series of three oceanographic survey cruises were conducted in June, July, and August of 2019 in the northeastern Gulf of Maine and Bay of Fundy. Surface water samples were collected and analyzed for enumerations of cell densities of the dinoflagellate Alexandrium catenella in relation to cell densities of diatoms. Hydrographic profiles of temperature, salinity, and nutrients (silicate and nitrate) were also made at each station. Data were analyzed to determine if there was any statistically significant evidence of allelopathic interference imparted by diatoms that impede A. catenella. A. catenella cells were most abundant in June, reaching 6,195 cells per …

The Effects Of Elevation On Foraging Behavior Of Bats In Southern Appalachia, Victoria Long

Electronic Theses and Dissertations

There are limited studies on bat activity in higher elevations in the Appalachian region. Levels of bat activity were compared in south central Appalachia at low (< 914.4 m) and high (> 1, 524 m) elevations in open, forest edge, and riparian habitats. Additionally, habitat suitability was modeled for a common species, big brown bat (Eptesicus fuscus). The study started May 27^th 2019, and sites were monitored biweekly until October 2^nd 2019. Six species and one genus were recorded during the study. Species from the Myotis genus were grouped together because of similar call characteristics. Results show that species were significantly more …

Determination Of The Summer Origins Of American Kestrels ( Falco Sparverius ) Wintering In Northern And Central Illinois, Taylor P. Joray

Theses and Dissertations

The seasonal and interannual movements of the American Kestrel (Falco sparverius) are not fully understood. Although one of the most widespread and abundant raptors found in North America, information on where many populations summer and overwinter is lacking. We used stable hydrogen isotope values obtained from feathers (δ2Hf) of known origin to create age-specific calibration functions for juvenile and adult American Kestrels. We then used these calibration functions to determine the most likely summer origins of the American Kestrels that wintered in northern and central Illinois during 2015-16, classified these individuals as year-round residents or wintering migrants, and validated these …

Influences Of Anti-Bd Bacteria On Amphibians And Their Microbiomes, Emme L. Schmidt

Honors Thesis

The fungal pathogen Batrochochytrium dendrobatidis (Bd) has been threatening amphibian populations across the globe. Recent work has discovered that bacteria isolated from certain populations of amphibians protect hosts from this pathogen. This project focuses on the anti-fungal mechanisms of Serratia marcescens, a species of bacteria isolated from a Costa Rican frog that dramatically inhibited Bd in culture. Wild-type and recombinant S. marcescens was introduced to the microbiomes of a live amphibian host, Acris blanchardi (Blanchard’s Cricket Frog) and then challenged with Bd to examine the protective effects of this bacteria. The experiment includes recombinant S. marcescens with …

A Genomic Analysis Of Bobcat Populations In North America With A Comparison To The Canada Lynx: An Assessment Of Local Adaptation To Unique Ecoregions And Phylogeography, Jennifer C. Broderick

Electronic Theses and Dissertations

Bobcats (Lynx rufus) are an ecologically and genetically diverse species with a large contiguous range throughout North America. The species not only has a wide array of phenotypic variation compared to other mammals, but shows marked adaptability across ecozones with differing ecological influences. It is these various selective pressures in distinctive parts of the continent that have likely led to localized adaptations within the bobcat metapopulations. The species is also marked by its ability to maintain connectivity and populations in anthropogenically developed areas, an advantage it has over other felids, including its close relative the Canada lynx ( …

Driver Of Avian Haemosporidian Diversity And Host Specificity In The Solomon Islands, Xena Marie Mapel

Biology ETDs

Avian haemosporidians are protist parasites that are distributed worldwide. We investigated these parasites in a tropical South Pacific archipelago to answer two questions: 1) Which community characteristics influence haemosporidian diversity; 2) Does host specificity vary across islands? To answer these questions we sequenced a mitochondrial gene and created linear models to establish relationships between select variables and diversity. In addition, we calculated host breadth of each lineage and constructed models to infer predictors of diversity. The percent of infected individuals on each island was correlated with island area. Haemosporidian phylogenetic diversity on a given island was associated with the proportion …

Detection Probability Of The American Marten (Martes Americana) In Michigan’S Lower Peninsula, Taylor Brian Root

Masters Theses

To accurately manage for the sustainability of wildlife populations, managers must first determine how to locate individuals of a population with great consistency. Determining the efficiency of detection techniques is a challenge, especially when the study species are scarce or elusive. Such is the case with the American marten (Martes americana), a small mustelid found across the Northern United States and Canada. In the lower peninsula of Michigan, marten are considered a species of concern, and the full extent of their range remains unknown. My goal was to test the efficacy of motiontriggered cameras for detecting the presence of American …

A Reexamination Of The Freshwater Mussel Community Of The Little Miami River, Emily Davis

Undergraduate Honors Thesis Projects

Understanding the changes in biodiversity and local freshwater mussel populations is critical to mitigate the risks to these populations. Freshwater ecosystems continue to degrade rapidly. The freshwater mussel community of the Little Miami River is degraded and has been in decline for many years. The biodiversity contained within freshwater ecosystems is lost at unprecedented rates influenced by human activity. Freshwater mussels play a key role in understanding the effects of human activity on freshwater ecosystems as well as maintaining the health of freshwater habitats. However, they are also sensitive to changes and disturbances, in their ecosystems. This study involved monitoring …

Diatom Voucher Flora And Comparison Of Collection Methods For Biodiversity Hotspot Upper Three Runs Creek, Katie M. Johnson

Biology Theses

Surface freshwater is a scarce resource. Due to the scarcity and necessity of this resource, it is imperative that its quality is routinely monitored. One way of monitoring water quality is through biological assessments, which include examining algal assemblages. Regionally, little remains known of algal taxa in the southeastern United States. In the past, the Academy of Natural Sciences of Philadelphia (ANSP) conducted biological assessments along the Savannah River finding Gomphonema parvulum (Kützing) Kützing 1849 to be a dominant taxon rendering assessments inconclusive. Recent studies have provided evidence that species complexes and semi-cryptic taxa have been identified within the Gomphonema …

The Mangroves Of Costa Rica, Kylie Stewart

Honors Projects

Mangroves are a type of coastal vegetation present in the intertidal zone of tropical and subtropical climates. This paper explores the mangroves of Costa Rica, their significance, and various strategies the country utilizes in order to protect mangrove forests. Several books and articles about mangroves and conservationism are examined to explain why mangrove forests are vital to a coastline’s health and growth. The scholarly topic pertains to mangroves located in the United States and Costa Rica along with methods used to maintain the wildlife that live within them. The concept of ecotourism will be explored and how mangrove forests are …

Current Dog Breeding Practices Impacts On Health And Preservation Of Purebred Dogs, Bridget E. Baker

Honors Theses and Capstones

No abstract provided.

Diet Of A Recently Reintroduced River Otter (Lontra Canadensis) Population In Taos County, New Mexico, Gabriela Alexandra Wolf-Gonzalez

Theses and Dissertations--Forestry and Natural Resources

North American river otters (Lontra canadensis), native to every U.S. state and Canada, experienced extensive population decreases and range reduction until the mid-20th century as a result of overexploitation and habitat loss during European colonization. The last known river otter in New Mexico was killed on the Gila River in 1953, although unverified reports continued thru 2008. After a nearly 60-year absence from New Mexico, 33 adult river otters were reintroduced to the Rio Pueblo de Taos in the northern part of the state between 2008-2010; however, they were not subsequently monitored or studied. I characterized diet of …

Spatial And Temporal Genetic Structure Of Winter-Run Steelhead (Oncorhynchus Mykiss) Returning To The Mad River, California, Steven R. Fong

Cal Poly Humboldt theses and projects

Distinct populations of steelhead in the wild are in decline. The propagation of steelhead in hatcheries has been used to boost population numbers for recreational fisheries and for use in conservation. However, hatchery breeding practices of steelhead can result in changes in genetic structure. I investigated the genetic structure of winter-run steelhead (Oncorhynchus mykiss) returning to the Mad River, California, where a hatchery has been used enhance production for recreational fisheries since 1971. Genetic variability in Mad River steelhead was evaluated using 96 single nucleotide polymorphisms (SNPs) among 4203 individuals, including the Mad River and nearby locations, and …

The Influence Of Land Use On The Pollen Diet Of Honey Bee (Apis Mellifera) Colonies In Ellis County, Kansas, Ryan Engel

Master's Theses

Pollinators are integral to plant ecology as well as to worldwide food availability and security. Understanding how human-driven land use change impacts the nutrition of managed honey bees is important in pollinator conservation efforts and can contribute towards combating recent pollinator declines. The objective of this study was to determine sources of forage for honey bees across different land use types in Ellis County, Kansas, through pollen analysis and taxonomic identification. Replicate study colonies were placed in three separate land use types: Urban, Cropland, or Native/Semi-native prairie. Pollen was sampled every 7 to 14 days throughout a growing season (April …