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Assessment Of Factors Influencing Migratory Landbird Use Of Forested Stopover Sites Along The Delmarva Peninsula During Autumn Migration, J. Andrew Arnold Dec 2020

Assessment Of Factors Influencing Migratory Landbird Use Of Forested Stopover Sites Along The Delmarva Peninsula During Autumn Migration, J. Andrew Arnold

Biological Sciences Theses & Dissertations

Autumn migration is a time when billions of birds move from breeding grounds in North America to wintering grounds in Central and South America, with many individuals relying on stopover habitats en route for resting and refueling purposes. These stopover sites are critical to the survival of the hundreds of species of migratory landbirds that migrate annually, and thus identifying important stopover sites is a high priority for conserving such taxa. The Delmarva Peninsula; a coastal region of Delaware, Maryland, and Virginia along the mid-Atlantic flyway; consists of forested habitats with ample food and shelter that likely serves as quality …


Global Conservation Status Of Croaker And Drum (Family: Sciaenidae) And Role Of The Maw Trade, Claire E. Gorman Dec 2020

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 …


Not Too Hot, Not Too Cold, But Moderately Variable: The Influence Of Environmental Variability On Coral Thermal Tolerance, Courtney Nicole Klepac Dec 2020

Not Too Hot, Not Too Cold, But Moderately Variable: The Influence Of Environmental Variability On Coral Thermal Tolerance, Courtney Nicole Klepac

Biological Sciences Theses & Dissertations

Anthropogenic climate change is causing an increase in the frequency and severity of marine heat waves, resulting in declining health of coral reef ecosystems worldwide. Coral bleaching events – the breakdown in symbiosis between the coral host and their intracellular photosynthetic algae – are increasingly common in recent years and contribute to widespread losses in coral cover. However, bleaching and heat stress responses vary across spatial scales both within and among coral species. Coral populations native to highly variable environments can have greater bleaching resistance than corals from more stable habitats and corals transplanted into these variable reef sites can …


Ixodes Scapularis Src Kinase Is Required For Rickettsial Pathogen Survival In Ticks, Jeremy W. Turck Dec 2020

Ixodes Scapularis Src Kinase Is Required For Rickettsial Pathogen Survival In Ticks, Jeremy W. Turck

Biological Sciences Theses & Dissertations

Anaplasma phagocytophilum is an obligate intracellular bacterium that causes disease in humans and animals. It is the causative agent for human anaplasmosis. A. phagocytophilum uses certain strategies to infect both vertebrates and invertebrates. It uses Ixodes scapularis ticks as a vector for spreading infection to other mammal species. This bacterium has a specific path for infection through the salivary glands of its vector host. It also suppresses certain functions such as the inhibition of apoptosis and ROS production in order to increase its survival in ticks. Src kinase, a non-receptor protein-tyrosine kinase, is a major player in cell signaling. Src …


Role Of Ixodes Scapularis Sphingomyelinase-Like Protein (Issmase) In Tick Pathogen Interactions, Pravesh Regmi Apr 2020

Role Of Ixodes Scapularis Sphingomyelinase-Like Protein (Issmase) In Tick Pathogen Interactions, Pravesh Regmi

Biological Sciences Theses & Dissertations

Arthropod-borne diseases are one of the major concerns throughout the world. Ixodes scapularis (hard tick) is one of the major vectors that is involved in arthropod-borne disease transmission. Langat virus (LGTV) is a model pathogen that is very similar to other medically important flaviviruses such as Tick-Borne Encephalitis virus (TBEV) and Powassan virus (POWV). Sphingomyelinase-like protein (IsSMase, a Sphingomyelinase D or SMase D, a venomous protein ortholog of spiders) is an enzyme present in ticks that helps to catalyze the hydrolysis of the sphingomyelin (cell membrane lipid) into phosphocholine and ceramide. The objective of our study is to delineate the …


Pthr1/Sox9 And Idh1/Idh2 Relative Expression In Primary Chondrocyte And Chondrosarcoma Cells Under The Synergistic Influence Of Inducible Hypoxia And Extracellular Acidosis, Kostika Vangjeli Apr 2020

Pthr1/Sox9 And Idh1/Idh2 Relative Expression In Primary Chondrocyte And Chondrosarcoma Cells Under The Synergistic Influence Of Inducible Hypoxia And Extracellular Acidosis, Kostika Vangjeli

Biological Sciences Theses & Dissertations

Cartilage cells (Chondrocytes) grow in rather unique environmental conditions in the human body. Cartilage is avascular tissue and lacks innervation. Its main source of nutrients is derived from the synovial fluid and/or perichondrium. Consequently, these cells must survive and thrive under hypoxic and acidic stressors. Published data suggests that there are a multitude of genes affected from either one of these two stressors or both. However, these factors are frequently overlooked in cartilage research, and results are reported in either normoxia/pH=7.0 conditions, or they only account for one of the conditions. The scope of this study is to examine how …


Diet Analysis Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Kristen Marie Volker Apr 2020

Diet Analysis Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Kristen Marie Volker

Biological Sciences Theses & Dissertations

This study describes the diet of bottlenose dolphins (Tursiops truncatus) stranded in Virginia via stomach content analysis and considers factors such as proportion of numerical abundance and reconstructed mass, frequency of occurrence, average reconstructed prey size, prey diversity and quantity, and otolith degradation code. Fish size was estimated via regression equations established from local fish collected during the study that derive wet weight directly from otolith length or width. Squid size is estimated from previously published equations. Soniferous fishes dominated the diet, especially Atlantic croaker, spot, and seatrout spp., adding evidence to the theory that bottlenose dolphins passively …


The Effects Of Hackberry Psyllids On Refueling Migratory Songbirds And Autumnal Seed Rain, Chance H. Hines Apr 2020

The Effects Of Hackberry Psyllids On Refueling Migratory Songbirds And Autumnal Seed Rain, Chance H. Hines

Biological Sciences Theses & Dissertations

Hackberry psyllids (Pachypsylla sp) are a galling insect native to North America’s hackberry trees (Celtis sp). Hackberry leaf-galling psyllids are ephemerally abundant during autumn, a period of time when migratory songbirds are traveling from their breeding areas in temperate North America south to their winter ranges. These migrations are energetically taxing and many songbirds fuel their journey with resources like insects and fruits. I captured birds with mist nets, observed foraging behaviors, and captured avian-dispersed fleshy fruit seeds (hereafter, seed rain) rain during the autumn of 2016 and 2017 to determine how hackberry psyllids, an ephemerally …