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Movement and migration ecology of Alaskan golden eaglesGolden eagles Aquila chrysaetos are distributed across the Holarctic; however, in Alaska and other northern areas, many are long-distance migrants. Being soaring birds, golden eagles can use weather and features of the energy landscape to offset the energetic costs of movement and migration. In this dissertation, I investigate how dynamic energy landscapes, in addition to other habitat and anthropogenic features, affect the movement and migration ecology of Alaskan golden eagles; in most cases I did such by developing and applying new, biologically-appropriate statistical methods. First, I identified a single, discrete navigation decision that each eagle made during migration and determined which weather variables are primary factors in driving that decision. I found that wind was the primary correlate to the decision, consistent with eagles likely avoiding poor migration conditions and choosing routes based on favorable wind conditions. Second, I investigated how different forms of flight subsidies, which were orographic uplift, thermal uplift, and wind support, drove behavioral budgets and migratory pacing of eagles. I found a consistent daily rhythm in eagle behavior and migratory pace, seemingly driven by daily development of thermal uplift, with extended periods of slower-paced movements, consistent with periods of opportunistic foraging. Third, I investigated the effects of anthropogenic linear features, such as roads and railroads, on eagle movement during migration. I found that eagles selected for roads during spring migration and were more likely to be near roads when making slower-paced movements, which would be most frequent during times when limited thermal uplift is available. Lastly, I compared how floaters (breeding-age, non-territorial individuals) and territorial eagles used space and selected for resources, specifically interested in how their movements and space use might overlap. I found that floater space use was much more expansive, yet they only selected for habitats and resources slightly differently than territorial eagles. I also found their home ranges overlap substantially, suggesting that floaters play a key role in the population ecology of migratory golden eagles in Alaska.
Characterizing wintertime aerosol composition and sulfate formation in Fairbanks, AlaskaThe citizens of Fairbanks, Alaska are exposed to high levels of air pollutants throughout the winter months, causing the city to violate the Fine Particulate Matter (PM₂.₅) National Ambient Air Quality Standards set in place by the United States Environmental Protection Agency. Previous studies have shown the significant amount of sulfate aerosols particles observed in Fairbanks winters, but the formation mechanism of aerosols containing sulfate in the atmosphere is still unknown. While sulfate aerosol particle formation is commonly driven by oxidants including ·OH, H₂O₂ and O₃, these photochemical species are limited in Fairbanks winter months. This indicates sulfate aerosol particle formation may occur through a nontraditional pathway, and this project investigates one proposed mechanism in which transition metals may catalyze sulfate aerosol particle formation. We collected twelve full diurnal cycles over the winter months of 2019, using a particle-to-liquid sampler (PILS) at hourly time resolution. This PILS instrument creates an aqueous extract containing only the water-soluble components of the aerosol particles. These aqueous extracts were analyzed offline for inorganic and metal concentrations by ion chromatography (IC) and inductively coupled plasma mass spectrometry (ICP-MS). This hourly dataset provides new insights in emissions, chemical processing and their coupling with boundary layer dynamics. We find a strong correlation between hourly sulfate and PM2.5 mass concentrations, but we do not find the strong evidence of transition metal ion (TMI) catalysis on sulfate formation. We also collected twelve sets of aerosol filters using Micro-Orifice Uniform Deposit Impactor (MOUDI) throughout the winter of 2019. These size-resolved filter samples suggest the presence of hydroxymethane sulfonate (HMS) in submicron particles when temperatures are below -30 °C (-22 °F), suggesting a new reservoir for sulfur compounds in Fairbanks winter and warranting further investigation.
The deadly affairs of John Figaro Newton or a senseless appeal to reason and an elegy for the dreamingAre you really you? Are your memories true? John "Fig" Newton thinks much the same as you do. But in three separate episodes of his life, he comes to see things are a little more strange and less straightforward than everyone around him has been inured to the point of pretending they are; maybe it's all some kind of bizarre form of torture for someone with the misfortune of assuming they embody a real and actual person. Whatever the case, Fig is sure he can't trust that truth exists, and over the course of his many doomed relationships and professional foibles, he continually strives to find another like him--someone incandescent with rage, and preferably, as insane and beautiful as he.
Diet composition and fate of contaminants in subsistence harvested northern sea otters (Enhydra lutris kenyoni) from Icy Strait, AlaskaNorthern sea otters (Enhydra lutris kenyoni) in Southeast Alaska have experienced a significant population increase since their successful reintroduction to the area after previous near extirpation owing to historic fur trading. The purpose of this study was to examine sea otter diet and metals contamination in an area of Southeast Alaska with the most robust increases in sea otter numbers, Glacier Bay/Icy Strait, with the intent of gathering baseline data for a healthy population of sea otters and as a reflection of the local coastal environmental health of the area. This research was a collaborative effort with Alaska Native subsistence hunters and the Alaska Department of Environmental Conservation. In Chapter 1, sea otter stomachs (n=25) were obtained in April 2015 and April 2016 from Alaska Native subsistence hunters in Icy Strait, Alaska. There were no differences in sea otter diet between years. Bivalves dominated the sea otter diet. Northern horsemussels (Modiolus modiolus) made up the greatest proportion of the diet (0.46 ± 0.48). Fat gaper clams (Tresus capax) and northern horsemussels were found in the highest proportion of stomachs (0.64 and 0.60, respectively). There was not an apparent trend between sea otter age and the minimum number of total prey items, stomach contents mass, or mean frequency of occurrence of the top four prey species. Sea otters from this study are likely to be dietary generalists throughout their lives. In Chapter 2, brain, gonad, kidney, and liver tissues, as well as stomach contents were analyzed for arsenic, cadmium, copper, lead, total mercury, and selenium for the 2015-harvested sea otters that were also referenced in Chapter 1 (n=14). In general, arsenic and lead had the highest concentrations in stomach contents, cadmium and selenium were highest in the kidneys, and copper and total mercury were highest in the livers. While brains and gonads had the lowest metals concentrations of any tissue, the metal with the greatest concentration within the brain was copper, and within the gonads was selenium. Concentrations of arsenic, cadmium, total mercury, and lead demonstrated a relationship with sea otter length. In general, all the mean metals concentrations for these sea otters were below published effects threshold values for marine mammals. Only total mercury demonstrated biomagnification from the stomach contents (i.e., the prey) to all higher-level tissues. Selenium health benefit values were positive in all sea otter tissue types analyzed in the present study, indicating that concentrations of selenium had an overall health benefit in protecting those tissues against mercury toxicity. Evaluating how contaminants concentrate and get distributed in tissues of top trophic levels provides an indication for potential exposure to humans and demonstrates how these keystone species act as indicators of local coastal ecosystem health. The results of studies on dietary exposure and metals contamination in top trophic level consumers such as sea otters can be used in monitoring the health of sea otter populations and the local environment that they inhabit.
Hearing colorsThis thesis project is the first part of a historical fiction novel. It takes place in the Outer Banks of North Carolina in 1910 and imagines the perspective of a sound-color synesthete named Bert Beasley, who witnessed the Wright brothers complete the first engine-powered flight. Bert wants to leave his home to pursue aviation but is unable to do so because he is needed to help run his family's failing general store. When Elisabeth Lavoie, a French musician, moves to town and buys a dilapidated house, Bert believes he'll be able to solve his problems by earning extra money as her repairman. However, her voice is purple--the only color he's never heard before--and her music changes colors, which shouldn't be possible. As he grows closer to Elisabeth, Bert becomes less sure that he wants to leave, but his decision is complicated once more when he learns that the Wright brothers have opened a flying school. The novel switches between the third-person points of view of Bert and Elisabeth. The dual perspectives provide insight into their individual inner conflicts--Bert longs to leave a home he loves as Elisabeth struggles to find a home she has lost--and demonstrates how their respective relationships with sound have shaped them into two people who have the potential to be a home for each other. The descriptions of synesthesia in this project present a creative interpretation of how color-sound combinations manifest themselves in synesthetes, both visually/audibly and emotionally. I conducted research to accurately portray the visual/auditory experiences of synesthesia, but I also took some artistic license in that the story implies that Bert's emotions, or the emotions of the musician playing the music he hears, has an effect on the color of the sound. This is not based on the known science of synesthesia but allowed for a deeper exploration of the characters' relationship and the question of home.