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Winter Abundance and Survival of Sharp-tailed Sparrows at the Eastern Shore of Virginia NWR: Final Report
No full textThe tidal saltmarsh habitat in the Chesapeake Bay region supports a diverse marsh sparrow suite during winter. Research on the status and distribution of these species has primarily focused on the breeding season despite the fact that winter accounts for a significant portion of songbird mortality. A lack of information about this period hampers our ability to conserve habitats that support birds. To better understand the factors that influence marsh sparrow winter ecology, we used capture-recapture sampling and double-pass rope drag transect surveys to explore parameters that affect winter mortality and density on the Eastern Shore of Virginia National Wildlife Refuge (ESVNWR) and Fisherman Island National Wildlife Refuge (FINWR). During the winter of 2020-2023, we captured 124 Nelson’s sparrows, 74 saltmarsh sparrows, and 24 seaside sparrows. Our top Cormack-Jolly-Seber model included a time-varying predictor that accounted for differential survival between the early and late portions of the winter, bird species, marsh identity, and an interaction between marsh and species within the survival function of the model with zero predictors in the recapture function. Recapture probability was estimated at 0.34 ± 0.07 SE. and daily survival ranged from 0.97-1.00, depending on species, study site, and winter period (early/late). Survival was higher during the early portion of winter for all species, possibly because seed availability declines throughout the winter. Survival was similar among all study sites for saltmarsh sparrows, highest for Nelson’s sparrows at the ESVNWR boat ramp marsh and highest for seaside sparrows at FINWR. We observed 226 sharp-tailed sparrows and 12 seaside sparrows on double-pass rope drag transects. We were unable to incorporate seaside sparrows into N-mixture models due to data deficiency. For saltmarsh and Nelson’s sparrows, survey site, survey season and an interaction between the two terms were included within the abundance function of our top model. Transect identity was included within the availability function of our top model and no predictors were included in the detection function. Detection was estimated at 0.86 ± 0.03 SE. Saltmarsh sparrow densities were between 0.6 – 1.3 birds per ha and were highest at a transect in ESVNWR Bull Marsh while Nelson’s sparrow densities were between 0.6 – 3.2 birds per ha and were highest at ESVNWR Boat Ramp Marsh. Saltmarsh and seaside sparrows were both associated with marshes with more cover and seed availability though saltmarsh sparrow densities were greatest in portions of the marsh further from the upland-marsh transition zone while seaside sparrows observations and survival were positively associated with marshes with taller vegetation like that found near the margins of tidal waterways. Nelson’s sparrows were associated with marsh that lacked attributes favored by saltmarsh and seaside sparrows, possibly to avoid interspecific competition. Some evidence for intra-specific habitat segregation also exists for Nelson’s sparrow as sex ratios skewed female at ESVNWR Boat Ramp Marsh and male at other field sites. The other two species of marsh sparrows had relatively even sex ratios at all sites
Textual Reasoning in Three Stages
No full textIn returning to textuality postmodern Jewish philosophy becomes textual reasoning. Educated by both the modality of rabbinic thought and the philosophy of pragmatism textual reasoning always begins with a life problem, a form of human suffering, an ethical dilemma which it attempts to address
Synthesis And Characterization Of Two Sets Of Group 12 Complexes With Organic Ligands
No full textThe complexes of group 12 elements are subjects of incredible interest due to differences in their bioactivity. Zinc is an essential element of life and is required for many bodily processes including gene production, growth, and the immune response. Cadmium and mercury are both toxic elements to humans. Part of their activity is due to their ability to replace zinc metal centers. Synthesis of new group 12 complexes can provide insight regarding their bioactivity and how replacement of metal centers can affect the structure of enzymes. In this thesis, the preparation and characterization of two sets of group 12 complexes is described. One set of new complexes are cadmium and mercury complexes of the N3S ligand 2-[bis(2-pyridinylmethyl)amino]ethanethiol (L1H) with chemical formulas [Cd(L1)Cl]2·benzene (1) and [Hg(L1)Cl] (2). They are compared with the known complex [Zn(L1)Cl] (3). The new complexes were thoroughly characterized using X-ray crystallography, XPRD, 1H NMR, elemental analysis, and IR. Compound 1 crystallized in the triclinic space group P-1 with an octahedral coordination geometry. The metal ions of 1 were bridged by a pair of ligand thiolate groups. Mononuclear compound 2 crystallized in the monoclinic space group P21/c with mixed square pyramidal/trigonal bipyramidal geometry (τ = 0.44). Both complexes are stabilized by significant offset face-to-face π−π and edge-to-face σ−π interactions between the pyridyl rings, and for 1, between the pyridyl rings and solvent benzene in the unit cells. Significantly, both complexes exhibit heteronuclear coupling in the 1H NMR at -40 °C between the metal centers and specific ligand protons indicating slow ligand exchange on the coupling constant time scale and unusual stability for thiolate complexes of these metal ions. The other set of isolated complexes are bis-tridentate chelates of Zn(ClO4)2, Cd(ClO4)2, and Hg(ClO4)2 with two equivalents of bis(2-pyridylmethyl) ether (L2). The complexes were characterized using X-ray crystallography, IR, 1H NMR, and TGA. [Zn(L2)2](ClO4)2·CH3CN (4) and [Cd(L2)2](ClO4)2·CH3CN (5) crystallized in the monoclinic space group P21 with meridional octahedral geometry. [Hg(L22)](ClO4)2 (6) crystallized with approximately C2 symmetric trigonal prismatic geometry. 1H NMR of 3 at 40 °C show heteronuclear JHgH coupling, and lacks the geminal splitting of methylene protons that would be expected for the solid-state structure. The complexes were compared to other bis-tridentate chelates of bis(2-pyridylmethyl) ligands with the central oxygen of L2 replaced by other heteroatoms.ChemistryMaster of Science (M.Sc.
Embodied Nature: Biomimetic Architecture as a Philosophy and Practice
No full textBiomimicry be defined simply as imitating elements and processes in nature and applying them to complex human problems. This paper will unpack this special term’s loaded meaning and rich past in much more detail, but by latching on to this fundamental concept of integrating organic forms in our engineering, we can glean strong parallels between human infrastructure and natural ecosystems. I adopt the view that biomimetic architecture, much like a habitat, operates on three different levels – organism, behavior, and ecosystem. I want to study how these scales of gel together, forming the main thrust of this ‘biotic’ design. Upon closer inspection of this special subset of “living” architecture there are several more questions and considerations that I look forward to researching: How have past and present architects sought inspiration from nature to inform their craft and to what extent? Beyond replicating organic forms aesthetically, is it also possible to mimic organic systems to further improve and innovate the function of buildings? In other words, can biomimetics allow architects to fully realize the potential of “earthly” engineering? Perhaps the answers found in this study will make the translation of biomimicry theory into practice more clear. I am confident that cross-connecting art, ecology, and technology will provide a comprehensive critique of biomimetics (and its relation to its counterparts like Green, Morphogenetic, Metabolic and Organic design) that could endorse this brand of architecture as a remedy to social and environmental challenges (such as overcrowding, industrial pollution, and unsustainable building practices).Art and Art HistoryBachelors of Arts (BA
Civic Virtue in Non-ideal Republics
Get PDFThis paper defends a neorepublican account of civic virtue as consisting of stable traits of character, understood in broadly Aristotelian terms, that exhibit excellences associated with the role of citizen, and that contribute to the secure protection of freedom as non-domination. Such an account is important for the neorepublican project because neither laws nor social norms can yield reliable support for republican freedom without a parallel input from civic virtue. The paper emphasizes the need to distinguish civic virtue from desirable norms, which can operate in tandem. Against other neorepublican accounts of civic virtue, it argues that the primary function of such virtue is not to support the stability of republican regimes. Rather, it has a corrective function, and may in fact challenge institutions, laws, and informal norms if they allow for the exercise of arbitrary power. Finally, the paper argues that this account of civic virtue is better positioned than a stability-focused account to shed light on the relationship between civic virtue and the common good.Philosoph
Climate Impacts On Spatiotemporal Habitat Usage Of Mid-Atlantic Fishes
No full textClimate change has altered marine environments, most notably by increasing water temperatures and reducing dissolved oxygen concentrations. These persistent changes have impacted the phenology and spatiotemporal habitat usage of mobile species, often through distributional shifts poleward or to deeper water. Climate-driven distributional shifts have been documented for numerous species inhabiting the Atlantic Ocean along the US East Coast, a region disproportionately affected by climate change. Adjacent estuaries are experiencing similar alterations to their physical environments and biotic community composition. Many estuarine species are seasonal residents and changes to environmental conditions within an estuary can result in altered usage and residence times. The Chesapeake Bay is one such estuary experiencing these climate-associated effects. The bay serves as an important habitat for a diverse array of seasonally resident marine and estuarine taxa, providing valuable foraging, refuge, and spawning grounds. Concurrent with physical changes, survey data have indicated decreases in relative abundance of many finfishes. However, environmental drivers associated with these declines have not been fully quantified. To evaluate the role of climate change on spatiotemporal habitat usage of Chesapeake Bay fauna, state-of-the-art statistical models were applied to several long-term monitoring data sets. Changes in Chesapeake Bay inhabitance by a suite of seasonally resident species were explored by evaluating estuarine-coastal ocean exchange and comparing the patterns to a more northern estuary, Delaware Bay. Relative habitat utilization of Chesapeake Bay declined for most species, while utilization patterns for Delaware Bay were largely constant or increasing over time. Broad-scale, multispecies analyses of relative habitat utilization time series revealed that the North Atlantic Oscillation, a signal of long-term warming, was an important driver of Chesapeake Bay exchange. Baseline habitat associations for several seasonal resident species in Chesapeake Bay were quantified through the development of ecological niche models. Model output indicated that impacts of climate change on environmental conditions of the bay, including continued increases in temperature and hypoxic volume, will likely exacerbate the decline in relative abundance. The niche envelopes were paired with an estuarine-carbon-biogeochemical regional ocean model to derive estimates of habitat suitability. The temporal patterns in habitat suitability did not match abundance trends, indicating that dynamics outside of the physical conditions of Chesapeake Bay are likely driving the decreased utilization of this estuary. Finally, the traditional mark-recapture modeling framework that includes catch-and-release fishing was extended to a subannual, multi-stock, spatially and temporally explicit version that allowed for simultaneous estimation of key parameters, including mortality rates and occupancy probabilities. Model estimated instantaneous natural mortality increased over time within Chesapeake Bay, particularly for older fish, but has not changed appreciably outside of the estuary, supporting previous findings of increased disease-associated mortality with age, and a possible role of climate change-associated suboptimal environmental conditions. Estimated occupancy probabilities exhibited differences in likelihood of estuarine inhabitance based on age, season, and producer region. Collectively, the results demonstrate heterogeneous changes in spatiotemporal habitat use of several Mid-Atlantic species on various scales. This information can be used by managers tasked with temporally and spatially dynamic policy development in a changing environment.Virginia Institute of Marine ScienceDoctor of Philosophy (Ph.D.