The study constructs a causal model of culinary tourist behavior from the theoretical framework of push and pull motivations and related concepts with regard to satisfaction and behavioral intentions. Respondents were distinguished with regards to socio-demographic characteristics, travel behavior, and importance of event attributes. Further, importance-performance hypothetical framework was utilized to measure pull motivations. The study proposed that culinary event attendees’ expenditures, word-of-mouth behavior, and repeat patronage intentions would be related to their overall event satisfaction. Culinary event attendees were segmented on the basis of push motivations. Using factor, cluster, and multiple regression analyses with data collected from an international culinary event, the study examined the above relationships. The results of the analyses can be summarized as: 1) food event, event novelty, and socialization were the push motivations identified for attending a culinary event, 2) motivations were clustered into two meaningful segments: Food Focusers and Event Seekers, 3) the two clusters statistically were different from each other based on gender, age, income, education, and expenditures, 4) on all event attributes, with the exception of nightlife, performance means were significantly lower than importance means, 5) food product, support services, and essential services had a significant predictive affect on overall satisfaction, and 6) overall satisfaction had a significant relationship with outcome variables (expenditures, word-of-mouth behavior, and repeat patronage). This research makes unique contributions to the area of consumer research in culinary tourism from both the theoretical and empirical perspectives. It is believed that results of the present study will be useful to organizers of culinary events and/or destination managers.

Although the X chromosome is usually similar to the autosomes in size, gene density and cytogenetic appearance, theoretical models predict that its hemizygosity in males may cause unusual patterns of evolution. The sequencing of several genomes has indeed revealed differences between the X chromosome and the autosomes in the rates of gene divergence, patterns of gene expression and rates of gene movement between chromosomes. In this thesis, I have attempted to investigate some of these patterns and their possible causes. The first two chapters consist of theoretical and empirical work intended to analyse the rates of evolution of coding sequences of X-linked and autosomal loci, with particular emphasis on faster-X evolution, the theory that more effective selection on the X can lead to higher rates of adaptive evolution on this chromosome. By analyzing X-linked and autosomal coding sequence in several species of Drosophila, we found some evidence for more effective selection on the X, particularly evident in the higher levels of codon usage bias detected at X-linked loci. We argue that this could be due to higher levels of recombination on the X chromosome increasing its effective population size (NeX) relative to the autosomal effective population size (NeA). To further investigate this hypothesis, we have modeled the effect of increased NeX/NeA on rates of evolution and confirmed that this can contribute to faster-X evolution. The last two chapters deal with the evolution of sex-biased genes and the possible causes for their differential accumulation on the X. We used EST data to create expression profiles for D. melanogaster male-, female- and unbiased genes. Our results suggest that the expression levels of sex-biased genes are incompatible with the accepted iii model of sex-biased gene evolution. We also show that the deficit of testis-expressed genes that is observed in Drosophila seems to be stronger for highly expressed genes. In fact, for very lowly expressed genes, we observe a small excess of testis-expressed genes on the X. We attempt to discuss this pattern in view of what is currently known about the evolution of sex-biased gene expression.

The snake genus Oligodon, known for its egg-eating feeding behaviour, is a taxonomically and systematically challenging group from South and Southeast Asia. This work provides the first phylogenetic hypothesis for the genus, and includes a checklist and key to the species. I use approximately 1900 base pairs of mitochondrial DNA sequence data to infer the relationships of these snakes, and I examine congruence between the molecular phylogeny and hemipenial characters. A hypothesis for the position of Oligodon within the Colubridae is also proposed. I discuss the implications of the phylogeny for previous taxonomic groupings, and consider the usefulness of the trees in analysis of behaviour and biogeography.

The snake genus Oligodon, known for its egg-eating feeding behaviour, is a taxonomically and systematically challenging group from South and Southeast Asia. This work provides the first phylogenetic hypothesis for the genus, and includes a checklist and key to the species. I use approximately 1900 base pairs of mitochondrial DNA sequence data to infer the relationships of these snakes, and I examine congruence between the molecular phylogeny and hemipenial characters. A hypothesis for the position of Oligodon within the Colubridae is also proposed. I discuss the implications of the phylogeny for previous taxonomic groupings, and consider the usefulness of the trees in analysis of behaviour and biogeography.

No description available.

Large gelatinous zooplankton (GZ) blooms of lobate ctenophores, Mnemiopsis leidyi, and scyphomedusae, Chrysaora quinquecirrha , occur throughout Chesapeake Bay and its tributaries. The mechanisms of GZ bloom formation, and the roles GZ blooms play in dissolved organic matter (DOM) and carbon (C) cycling are not fully understood. During 2003--2006, I conducted laboratory experiments and field surveys in the lower York River to determine factors controlling timing and magnitude of GZ blooms, and to evaluate their effects on C cycling. Highest biomass of M. leidyi occurred in early summer (May-June) and in late winter. Peaks in ctenophore biomass in the mesohaline region occurred one-month earlier than in downriver, polyhaline regions, due to higher ctenophore reproduction and larval dispersal upriver. High predation by C. quinquecirrha scyphomedusae on M. leidyi appears to cause the rapid decline in summer ctenophore blooms, and we hypothesize that subsequently medusae become C-limited. High GZ biomass coincides with peaks in microbial biomass, and as DOM is released by zooplankton but consumed by bacteria, these disparate trophic levels may be linked. I measured DOM production by GZ and the response of free-living bacterioplankton to GZ DOM, quantified in terms of bacterial metabolism, and bacteria phylogenetic community composition. Release rate of DOC by both GZ species was high relative to simultaneous release of DON and DOP, and for M. leidyi DOM metabolites were C-rich due to high mucus production in ctenophores. Furthermore, bacterioplankton abundance and production rapidly increased (within 6 hours) in response to uptake of GZ metabolites; however, decreases in bacterial growth efficiencies indicated that increases in bacterial C respiration were greater relative to changes in bacterial biomass. Enumeration of microbial assemblages using the fluorescence in situ hybridization (FISH) technique showed specific bacterial groups, namely gamma-proteobacteria, are responsible for increased metabolism of GZ DOM metabolites. In the context of worldwide increases in GZ, my results have significant implications for C transfer in marine food webs, with the potential for more C to be shunted to the microbial loop away from higher trophic levels.

Environmental conditions may positively or negatively influence production, reproduction, and restoration of submerged aquatic vegetation (SAV). As SAV populations decline, it is important to understand the potential impacts of the environment on the natural processes of reproduction. The objectives of this study are to provide fundamental information on sexual reproduction in a dominant species of freshwater SAV, Vallisneria americana, in the Chesapeake Bay observe the changes in environmental conditions in an established V. americana bed over an entire growing season (April-October), quantify the effects of similar environmental conditions on V. americana seed germination under controlled laboratory conditions, and finally to synthesize this information in order to develop a series of criteria for V. americana restoration in the Chesapeake Bay. Light, dissolved oxygen, temperature, salinity, sediment composition, V. americana production (biomass, density) and reproduction (flowering) were measured in a persistently vegetated SAV bed located in a tidal freshwater tributary to the Chesapeake Bay over the 2004 growing season. In addition, the effects of these same parameters on germination of V. americana seeds were quantified separately under controlled laboratory conditions. Production of V. americana biomass in Nanjemoy Creek increased significantly when water temperatures increased above a threshold of 25 ºC. Flowering occurred during periods of peak biomass (August and September) and resulted in the production of up to 71 seed pods m-2 at the end of the growing season. Despite the potential production of thousands of seeds m-2, < one percent were retained in the seed bank and remained viable after a period of 12 months. Germination of V. americana seeds was enhanced (greater overall germination and shorter time to germination) under oxygenated conditions, at temperatures > 22 ºC, at salinities of 0 psu, and when sediments were composed of ≤ 3 percent organic content and > 40 percent sand. Light (< 160 μmol m-2 s-1) and burial depth (down to 10 cm) had no significant effect on germination. Based on the synthesis of field and laboratory data, criteria for restoration of V. americana using seeds in Chesapeake Bay should include temperatures greater than 13 ºC, salinities ≤ 5 psu, and sediment containing ≤ 3 percent organic content and > 40 percent sand. This research provides the initial steps to determine which environmental factors affect germination of V. americana seeds and may increase the efficiency of current restoration practices for this species and provide a mechanism for increased success of current and potential larger scale projects.

Variation in a male ability to gain extra-pair paternity and maintain within-pair paternity are important sources of variation in male fitness in socially monogamous species and thus become the resource of sexual selection on male secondary sexual traits. While the maximum possible number of offspring sired within the social pair-bond is limited by the female’s clutch size, the possible number of sired extra-pair young could in theory by much higher. The crucial question then becomes why males not invest all their efforts into seeking matings with many females rather than investing in social pair bonds in terms of mate guarding and expensive paternal care of offpring? I examined the distribution and relationship between maintained within-pair paternity and gained extra-pair paternity in other males’ nests in a passerine bird, the collared flycatcher, in relation to age, body mass, tarsus length, and forehead patch size . There was no correlation between gaining extra-pair paternity in other males’ nests and keeping within-pair paternity within the own nest. Variation in maintained paternity has a slightly larger effect than gained paternity on variation in total male siring success (fitness) in our population. The overall number of offspring sired was not associated with body mass, patch size, or male age. These results indicate that ensuring paternity by mate guarding of a social mate may be important for male reproductive success.

I used 1.75 m&\sp2& drop rings and throw rings to sample communities of nekton at high and low tides in contiguous salt marshes, unvegetated flats, and seagrass beds (Ruppia maritima) of lower Chesapeake Bay. Thirty-two species of nekton were captured between June and October 1995, with a mean overall abundance of 28.6 inds m&\sp{lcub}-2{rcub}& and a mean biomass of 3.8 g m&\sp{lcub}-2{rcub}& (dry weight, dw). Blue crabs, Callinectes sapidus, were the biomass dominants and used seagrass and marsh edge habitats extensively from recruitment to maturity. Palaemonetes shrimp were the most abundant nekton; patterns of allopatry and apparent sympatry were found among the three species present. Menidia menidia used the marsh surface at night. Behavioral patterns for marsh residents Fundulus heteroclitus, F. majalis, Lucania parva, Gobiosoma bosc, and P. intermedius differed from patterns reported elsewhere. This suggests behavioral flexibility in habitat use between regions. Seagrass and marsh edges supported a large biomass of nekton. Secondary production on the marsh surface was estimated at 7.4-8.0 gdw m&\rm\sp{lcub}-2{rcub}150\ d\sp{lcub}-1{rcub}& (28.4-30.7 gww m&\rm\sp{lcub}-2{rcub}150\ d\sp{lcub}-1{rcub}&) between June and October 1995 (150 days). Gut contents of predators were examined, and a mathematical model was constructed to estimate consumption and export by nekton. Predation on invertebrates was highest in marsh edge areas, at 44.2 gdw m&\rm\sp{lcub}-2{rcub}150\ d\sp{lcub}-1{rcub}& removed; predation at the edge by transients (export) was 28.0 gdw m&\rm\sp{lcub}-2{rcub} 150\ d\sp{lcub}-1{rcub}.& The value of marsh edge was clearly linked to both vegetated and unvegetated components as refuge and feeding. Predation in the entire marsh was approximately 13 gdw m&\rm\sp{lcub}-2{rcub} 150\ d\sp{lcub}-1{rcub},& and transient export was 5.6 gdw m&\rm\sp{lcub}-2{rcub} 150\ d\sp{lcub}-1{rcub}.& Most export from marsh interior habitats was via blue crab predation on Uca and Sesarma. Predation in unvegetated areas was 13.3-17.0 gdw m&\rm\sp{lcub}-2{rcub} 150\ d\sp{lcub}-1{rcub};& export was 8.0-11.7 gdw m&\rm\sp{lcub}-2{rcub}150\ d\sp{lcub}-1{rcub}.& The unvegetated intertidal was an important resource for nekton due to lengthy inundation and abundant polychaete prey. The trophic contribution of each habitat was significant. Marsh, unvegetated, and seagrass habitats function together in this area to provide feeding and refuge for intertidal nekton.

Cobia (Rachycentron canadum) is a cosmopolitan marine fish inhabiting tropical, sub-tropical, and temperate marine and estuarine waters. Recent changes in U.S. cobia management have sparked controversy and highlighted limitations in our understanding of seasonal movement patterns and problems with estimating recreational harvests. Consecutive years (2015 and 2016) of estimated overharvests from the Atlantic Migratory Group stock triggered accountability measures to prevent overfishing by recreational anglers. My project employed pop-up satellite archival tags (PSATs) to study cobia movements, habitat utilization, and post-release survival. It was, therefore, designed to enhance knowledge of cobia biology and aid sustainable management. We deployed 36 PSATs on cobia caught in Virginia state waters using standard recreational techniques in August 2016 and August – September 2017. All fish larger than 37- inches total length were tagged, and several of these were deep-hooked. No mortalities were inferred from the 24 cobia whose PSATs reported. Only five PSATs remained attached until the 180-day programmed release date. This made it difficult to accurately describe cobia seasonal movement patterns, although it appears that areas near North Carolina's continental shelf break may be important overwintering habitat. Other overwintering areas may exist, however, as some fish made longer migrations, and one PSAT reported in Florida waters (beyond the current stock demarcation boundary). Cobia have a strong affinity for waters ≥20°C, even in the coldest months. They also display distinct seasonal differences in vertical movement patterns which make them more susceptible to capture in the summer when Virginia recreational anglers often employ sight-fishing techniques.