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Occurrence Of The Oyster Parasite, Haplosporidium Nelsoni, In The Damariscotta River Estuary, Maine, Nicole Messerman Dec 2014

Occurrence Of The Oyster Parasite, Haplosporidium Nelsoni, In The Damariscotta River Estuary, Maine, Nicole Messerman

Electronic Theses and Dissertations

Haplosporidium nelsoni is a protozoan parasite that causes the devastating disease MSX in the Eastern oyster, Crassostrea virginica, along the East coast of the United States. Until recently, H. nelsoni had not reached epizootic levels in Maine. However, in the summer of 2010, H. nelsoni was responsible for significant mortalities in cultivated Eastern oysters in the Damariscotta River Estuary. Since the initial outbreak, surveys performed by the Department of Marine Resources (DMR) show that MSX is still prevalent in the Damariscotta River Estuary. The industry remains concerned about the parasite levels with each new grow out season. In this study, …


Evaluation Of Airborne Lidar As A Tool For Obtaining Sustainable Forest Management Of Maine's Forests, Rei Hayashi Dec 2014

Evaluation Of Airborne Lidar As A Tool For Obtaining Sustainable Forest Management Of Maine's Forests, Rei Hayashi

Electronic Theses and Dissertations

The first objective of this study was to evaluate the applicability of using a low density (ca. 1 point m􀀀2) discrete-return LiDAR for predicting maximum tree height, stem density, basal area, quadratic mean diameter, and stem volume using an area-based approach. The research was conducted at the Penobscot Experimental Forest in central Maine, where a range of stand structures and species composition is present and generally representative of northern Maines forests. Using a variety of high dimensional LiDAR metrics, a prediction model was developed using random forest, a nonparametric approach, based on reference data collected in fixed radius circular plots. …


Using Migration Monitoring Data To Assess Bird Population Status And Behavior In A Changing Environment, Evan M. Adams Dec 2014

Using Migration Monitoring Data To Assess Bird Population Status And Behavior In A Changing Environment, Evan M. Adams

Electronic Theses and Dissertations

Across the world, researchers use migration banding stations to document bird migration and study the phenomenon. In this dissertation, I focus on ways of analyzing bird migration banding data and the utility migrating birds as indicators of ecosystem health that make these monitoring efforts more useful to answering ecological questions and managing migratory species. In Chapter 1, we provide background on hierarchical modeling and an overview of our findings. In Chapter 2, we developed and validated new methods to estimate daily changes in migratory population size while controlling for changes in detectability due to environmental conditions. In Chapter 3, this …


Amphibians In Complex Landscapes: Quantifying Habitat Connectivity For Juvenile Movements And Dispersal, Brittany Blue Cline Aug 2014

Amphibians In Complex Landscapes: Quantifying Habitat Connectivity For Juvenile Movements And Dispersal, Brittany Blue Cline

Electronic Theses and Dissertations

Maintaining amphibian populations in fragmented landscapes depends on preserving functional connectivity for animals that need to transit multiple vegetation types to satisfy habitat requirements. For many pool-breeding amphibians, successful dispersal is essential for gene flow; thus, quantifying the ability of juveniles to locate and reach suitable habitat in the terrestrial matrix is necessary to predict the consequences of landscape configuration for populations. I evaluated if different open-canopy vegetation types alter the behavior of juvenile wood frogs (Lithobates sylvaticus). First, I quantified the relative permeability of different open-vegetation types by experimentally releasing frogs in 35 x 3 m enclosures extending from …


Developmental Cis-Regulatory Analysis Of The Cyclin D Gene In The Sea Urchin Strongylocentrotus Purpuratus, Christopher Michael Mccarty Aug 2014

Developmental Cis-Regulatory Analysis Of The Cyclin D Gene In The Sea Urchin Strongylocentrotus Purpuratus, Christopher Michael Mccarty

Electronic Theses and Dissertations

Proper execution of animal development requires that it be integrated with cell division. In part, this is made possible due to cell cycle regulatory genes becoming dependent upon developmental signaling pathways that regulate their transcription. Cyclin D genes are important bridges linking the regulation of the cell cycle to development because these genes regulate the cell cycle, growth and differentiation in response to intercellular signaling. In this dissertation, a cis-regulatory analysis of a cyclin D gene, Sp-CycD, in the sea urchin, Strongylocentrotus purpuratus, is presented. While the promoters of vertebrate cyclin D genes have been analyzed, the cis-regulatory sequences across …


Maine Farmers' Perspectives: Barriers And Optimism To Providing Food To Feed Maine People, A Qualitative Study Using Focus Groups, Kelly Ann Ilseman May 2014

Maine Farmers' Perspectives: Barriers And Optimism To Providing Food To Feed Maine People, A Qualitative Study Using Focus Groups, Kelly Ann Ilseman

Electronic Theses and Dissertations

Maine has a history and tradition of agriculture in the state. Some growth in the number of farms in recent years has been due to youth entering agriculture, and in the development of small, diverse farms. There is also public interest in purchasing fresh, local foods. This study was done in conjunction with a University of Maine Cooperative Extension study that assessed Maine farmer’s views of the future of farming in Maine. The farmers (n=189) participated in one of twelve focus groups held across the state and represented a broad sector of Maine agriculture, including vegetable and fruit growers, beef …


Application Of Spatial Modeling Tools To Predict Native Bee Abundance In Maine's Lowbush Blueberries, Shannon J. Chapin May 2014

Application Of Spatial Modeling Tools To Predict Native Bee Abundance In Maine's Lowbush Blueberries, Shannon J. Chapin

Electronic Theses and Dissertations

Non-native honeybees historically have been used to pollinate many crops throughout the United States, however, recent population declines have revealed the need for a more sustainable pollination plan. Native bees are a natural resource that can play an important role in pollination. I used spatial modeling tools to evaluate relationships between landscape factors and native bee abundance, with a focus on the wild native bees that pollinate Maine’s lowbush blueberries. I applied the InVEST Crop Pollination ecosystem spatial modeling tool, which predicts pollinator abundance based on available floral resources and nesting habitat, to the Downeast Maine region. The InVEST model …


Spatial And Habitat Responses Of Canada Lynx In Maine To A Decline In Snowshoe Hare Density, David G. Mallett May 2014

Spatial And Habitat Responses Of Canada Lynx In Maine To A Decline In Snowshoe Hare Density, David G. Mallett

Electronic Theses and Dissertations

Previous studies of Canada lynx (Lynx canadensis) within the northern boreal forest region have documented that lynx respond spatially to a decline in snowshoe hare (Lepus americanus) density, as exhibited by expansion of territories and changes in social structure. I compared home range area and spatial overlap in the southeastern portion of their geographic range during periods of relatively high and relatively low hare density. Home range areas of lynx did not change between periods of high and low hare density, except that home ranges of females during the denning season expanded during the low period. The presence of kittens …


Effects Of High Pressure Processing On The Quality Of Farm-Raised Abalone (Haliotis Rufescens), Brianna H. Hughes May 2014

Effects Of High Pressure Processing On The Quality Of Farm-Raised Abalone (Haliotis Rufescens), Brianna H. Hughes

Electronic Theses and Dissertations

High pressure processing (HPP) is a non-thermal method used to increase food safety and shelf-life. HPP has been explored for meat tenderization, with conflicting results depending on rigor status during HPP. In the seafood industry, HPP is used to shuck oysters and lobsters, but has been minimally investigated for use in processing abalones. Abalones are shellfish with high perishability that are typically sold live or frozen in the U.S. HPP has been proposed as an alternative method to process shucked abalone meats. The objectives of this research were to evaluate the effects of 1) rigor status during HPP on abalone …