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An Analysis Of Gulf Of Maine Cod Metapopulation Structure And Localized Stability, With Application To Area-Based Fisheries Management, Derek Olson

Electronic Theses and Dissertations

The complex metapopulation structure of groundfish stocks in the Gulf of Maine, particularly Atlantic cod (Gadus morhua), is largely ignored under the current system of broad-scale stock assessment and management. This mismatch of biological and administrative scales has contributed to severe overall stock decline and localized serial depletion of Gulf of Maine cod. Such chronic management failure has led to growing calls for a more area-based, finer-scale approach to managing groundfish in the Gulf of Maine. A primary difficulty hindering the development of finer-scale groundfish management has been the challenge of estimating fishing mortality upon local stock components. …

The Forgotten Cousin In Freshwater Community Ecology: Tidal Freshwater Wetlands, Jack R. Mclachlan

Electronic Theses and Dissertations

Tidal freshwaters are unique in their placement in the landscape, forming where freshwater riverine flows are sufficient to overwhelm the saline water of the incoming tide, but not strong enough to suppress tidal water-height fluctuations. Tidal freshwaters and their wetlands have been overlooked by freshwater and marine researchers alike; neither discipline considers tidal freshwaters to fall under their purview. Invertebrate communities in tidal freshwaters are thought to be species depauperate; the consensus is that they support fewer taxa than nearby non-tidal freshwaters, but little is known about how these communities are structured. This study investigated how tidal hydrology, an atypical …

Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos

Electronic Theses and Dissertations

Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because clearance-rate measurements are affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clams Mya arenaria and Mercenaria mercenaria and the tunicate Ciona intestinalis, calculated using a direct method …

Chemical And Non-Chemical Control Of Potato Pink Rot, Xuemei (Missi) Zhang

Electronic Theses and Dissertations

Pink rot of potato (Solanum tuberosum) is a widespread soilborne disease that causes significant losses in the field and storage. It is caused by Phytophthora erythroseptica (Pethybr.), an oomycete pathogen that produces sexual spores that can survive in soil for years. The management of pink rot mainly relies on chemical control. However, the most effective chemical in pink rot control, mefenoxam, is losing its efficacy owing to the development of mefenoxam resistance in P. erythroseptica. To evaluate alternative fungicides (including chemical and biological fungicides) to mefenoxam in pink rot control, two greenhouse experiments and three field trials …

Investigating The Relationship Among Sleep, Stress, And Body Mass Index In At-Risk First-Year College Students, Grace A. Violette

Electronic Theses and Dissertations

The study objective was to investigate relationships among body mass index (BMI), sleep quality/duration, and perceived stress in 1,176 first semester college students who enrolled in Get Fruved, an 8-state social marketing intervention to prevent unwanted weight gain. Research was limited to first-year college students at-risk for unwanted weight gain. Eligibility was based on self-report of inadequate fruit and vegetable intake and subjects meeting one or more health-risk criteria (e.g., high BMI). Students (mean age=181 years; 65% white) completed physical measurements and an online survey, including the Pittsburgh Sleep Quality Index (PSQI) (score range 0-21; ˃5=disordered sleep) and the Cohen …

Environmental Dna Detection Of Invasive Species, Geneva York

Electronic Theses and Dissertations

Invasive species cause catastrophic changes to environments they are introduced into. Early detection offers the best chance at controlling the spread and mitigating any potential damages caused by the invaders. Environmental DNA (eDNA) has emerged as a more sensitive and cost effective alternative to traditional survey approaches to detection. In this study, I designed primer-probe sets for use in quantitative PCR detection of three invasive Centrarchid species, Largemouth Bass (Micropterus salmoides), Smallmouth Bass (Micropterus dolomieu) and Black Crappie (Pomoxis nigromaculatus). I surveyed 21 water bodies in Maine during two seasons (winter and spring). I …

Preparing For Effective Program Dissemination And Implementation: An Analysis Of Problems And Proposals For The Icook 4-H Program, Jodi L. Randall

Electronic Theses and Dissertations

While much effort has gone into the creation of obesity prevention programs like iCook 4-H, such programs remain largely under-utilized. The disconnect between research and practice highlights the necessity of dissemination and implementation strategies to ensure programs become adopted into practice. Creating a well-informed systematic approach to implementation will ensure that the iCook 4-H program will be implemented efficaciously and sustainably to improve the health of generations to come. The goal of this research was to implement the pilot dissemination and describe the findings in the context of the Quality Implementation Framework. The objectives were to report outcomes of the …

Investigating High Speed Localization Microscopy Through Experimental Methods, Data Processing Methods, And Applications Of Localization Microscopy To Biological Questions, Andrew J. Nelson

Electronic Theses and Dissertations

Fluorescence Photoactivation Localization Microscopy(FPALM) and other super resolution localization microscopy techniques can resolve structures with nanoscale resolution. Unlike techniques of electron microscopy, they are also compatible with live cell and live animal studies, making FPALM and related techniques ideal for answering questions about the dynamic nature of molecular biology in living systems. Many processes in biology occur on rapid sub second time scales requiring the imaging technique to be capable of resolving these processes not just with a high enough spatial resolution, but with an appropriate temporal resolution. To that end, this Dissertation in part investigates high speed FPALM as …

Old-Growth Characteristics Of Northern White-Cedar Stands, Nathan Wesely

Electronic Theses and Dissertations

Northern white-cedar (Thuja occidentalis; hereafter white-cedar) communities have received relatively little research attention, and managers lack the tools used in the management of other commercial tree species. This includes the recognition of old-growth characteristics and the differentiation between old-growth and partially harvested stands, particularly in the context of Forest Stewardship Council (FSC-US) certification. Specifically, there is very little information about characteristics that define old-growth white-cedar stands despite the species’ abundance and wide distribution. Regional indices for late-successional or old-growth stands (Whitman and Hagan, 2007) do not include white-cedar. Forests dominated by white-cedar represent a type that currently lacks …

Hydroacoustic Analysis Of The Effects Of A Tidal Power Turbine On Fishes, Haley Viehman

Electronic Theses and Dissertations

Tidal currents help shape coastal marine environments and are essential in life cycles of many fish species. Areas with strong tidal currents are also targeted by humans for energy extraction via tidal energy turbines. The effects of these devices on fishes are difficult to predict because fish behavior within fast tidal currents is largely unstudied. Based at a tidal energy site in Cobscook Bay, Maine, this work sought to describe fish reactions to a tidal energy device, to understand the natural presence of fish at the site, and to provide guidance for future monitoring of tidal energy device effects in …

Modeling And Forecasting The Influence Of Current And Future Climate On Eastern North American Spruce-Fir (Picea-Abies) Forests, Caitlin Andrews

Electronic Theses and Dissertations

The spruce-fir (Picea-Abies) forest type of the Acadian Region is at risk of disappearing from the United States and parts of Canada due to climate change and associated impacts. Managing for the ecosystem services provided by this forest type requires accurate forecasting of forest metrics across this broad international region in the face of the expected redistribution of tree species. This analysis linked species specific data with climate and topographic variables using the nonparametric random forest algorithm, to generate models that accurately predicted changes in species distribution due to climate change. A comprehensive dataset, consisting of 10,493,619 observations …

Linking Rising Pco2 And Temperature To The Larval Development, Physiology And Gene Expression Of The American Lobster (Homarus Americanus), Jesica Waller

Electronic Theses and Dissertations

Anthropogenic warming and ocean acidification are occurring as CO₂ continues to accumulate in the atmosphere (OA). Few studies have evaluated the joint effects of elevated temperature and partial pressure of CO₂ (pCO₂)on marine organisms. In this study we investigated the interactive effects of Intergovernmental Panel on Climate Change (IPCC) predicted temperature and pCO₂ for the end of the 21st century on key aspects of larval development of the American lobster, Homarus americanus, an otherwise well-studied, iconic, and commercially prominent species in the northeastern United States and Atlantic Canada. Our experiments showed …

Understanding The Impact Of Commercial Harvest On White Suckers (Catostomus Commersonii) In Maine, Megan A. Begley

Electronic Theses and Dissertations

The State of Maine issues an unlimited number of commercial permits for the harvest of White Suckers Catostomus commersonii in Maine’s inland waters. The fishery provides a necessary source of fresh lobster Homarus americanus bait to coastal communities at a time when other bait sources are scarce. The impacts of the increasing number of permits and subsequent numbers of fishermen on the white sucker population is unknown. The Maine Department on Inland Fisheries and Wildlife (MDIFW) has closed a number of waters due to concerns that overfishing and incidental catch of other fish species may occur.

In Chapter 1, we …

The Effects Of A Wild Blueberry Diet On Hepatic And Aortic Morphology In The Obese Zucker Rat, A Model Of The Metabolic Syndrome, Thomas Merrow

Electronic Theses and Dissertations

The goal of this study is to investigate the effect of a wild blueberry diet on pathology of the metabolic syndrome (MetS) by examining the morphological and biochemical properties of the liver and aortic tissue in the obese Zucker rat (OZR), a valid model of the MetS.

At 8-weeks of age, 16 Obese Zucker ras (OZR) and 16 lean Zucker rats (LZR) littermates were placed on either an 8% w/w wild blueberry (WB)-enriched isocaloric diet or an isocaloric control (C) diet for a duration of 8-weeks. At 16-weeks of age, the tissues of interest were harvested for the study. The …

Social Ecological Food Systems: Sustainability Lessons From Maine Dairy Networks, Julia B. Mcguire

Electronic Theses and Dissertations

Milk production has played an integral role in the culture, landscape, and economy of Maine’s agriculture. Maine dairy farmers have faced numerous sustainability challenges to economic, environmental, and social aspects of their industry. Like many other complex social ecological systems, the Maine dairy industry faces a gap between scientific knowledge and actionable management or policy. A cultural dichotomy exists between conventional and organic farming. Shifting the focus from this binary, metrics such as social capital may play a key role in solving sustainability issues. Difficulties arise in the governance of complex social ecological systems when the scales of assessment, management, …

Shortnose Sturgeon (Acipenser Brevirostrum) Spawning Potential In The Penobscot River, Maine: Considering Dam Removals And Emerging Threats, Catherine Johnston

Electronic Theses and Dissertations

Dam removals from the Penobscot River in Maine restored access to freshwater habitat critical for the life cycle of endangered shortnose sturgeon. Prior to the dam removals, shortnose sturgeon spawning activity had not been documented. Instead, evidence suggested that individuals emigrated from the Penobscot River to spawn in the Kennebec complex, 140 km away. A central question of this thesis was whether spawning activity would commence in the first two years following dam removal. Consistent with pre-dam removal movement patterns determined using acoustic telemetry, the majority (78%) of tagged individuals emigrated from the Penobscot River at some point over the …

Propagation And Container Production Of The Amelanchier Spicata Complex, Gregory J. Melcher

Electronic Theses and Dissertations

Amelanchier is a genus in the Rosaceae containing shrubs and trees indigenous to North America that possess traits valued by the horticulture industry. Amelanchier spicata (dwarf serviceberry), a heterogeneous complex of hybrids indigenous to eastern North America, has agricultural and ornamental merit with notable characteristics. White blossoms emerge in early spring, edible pomes ripen in the summer, and vibrant, orange foliage occurs in the fall. I investigated phenological and physiological factors influencing adventitious rooting of stem cuttings, the effects of nitrogen source on the development of seedlings grown in container culture, and phenotypic variation among seedlings of A. spicata from …

Population Genetic Structure Of Softshell Clams (Mya Arenaria) With Regard To A Saxitoxin-Resistant Mutation And Neutral Genetic Markers In The Gulf Of Maine, Jennifer Phillips

Electronic Theses and Dissertations

The softshell clam, Mya arenaria, is a commercially important bivalve species that is found in soft-bottom intertidal habitats throughout the Gulf of Maine, USA. This species is subjected to seasonal blooms of the toxic algae Alexandrium spp., and acts as a vector for paralytic shellfish poisoning (PSP) during harmful algal bloom (HAB) events. Some clams possess a naturally occurring genetic mutation of their voltage-gated sodium channels that grants them a resistance to the paralytic effects of saxitoxin (STX) produced by Alexandrium spp. The mutation allows these individuals to continue feeding during HABs, and greatly increases their tissue toxicity through …

Dynamic Host-Pathogen Interactions Result In Fungal Epitope Unmasking, Alex Hopke

Electronic Theses and Dissertations

Molecular camouflage is used by a diverse set of pathogens to disguise their identity and avoid recognition by protective host receptors. The opportunistic fungal pathogen Candida albicans is a good example, as it masks the inflammatory component β-glucan in its cell wall to evade detection by the immune receptor Dectin-1. Interestingly, it has been seen that β-glucan becomes unmasked during infection in vivo, though the underlying mechanisms remained unclear. Exposure levels of this epitope may be important, as Dectin-1 mediates protection from some strains of C. albicans and alterations in the organization and composition of the Candida cell wall …

Refrigerated Shelf Life Evaluation And Effects Of Minimal Processing On Antioxidant Capacity Of Fresh Sea Vegetables From New England, Dhriti Nayyar

Electronic Theses and Dissertations

Sea vegetables (also known as seaweeds) are gaining popularity among American consumers as a new superfood. Some sea vegetable farmers in New England have begun to distribute fresh or minimally processed sea vegetables to local restaurants and to retail distributors. However, limited knowledge about quality loss and processing effects on fresh, farm-raised sea vegetables postharvest obstructs the growth of a vibrant sea vegetable industry. The objectives of this research were to: 1) evaluate the quality changes and shelf life of four fresh sea vegetables species - dulse, Gracilaria, sugar kelp and winged kelp - during refrigerated storage, 2) determine the …

Size As A Trait For Understanding The Role Of Zooplankton In The Biological Carbon Pump, Karen Stamieszkin

Electronic Theses and Dissertations

Living organisms impact carbon transport between the atmosphere and the ocean through the biological carbon pump. Some plankton communities augment carbon export from the ocean’s surface, and are thought to have a major role in global climate. These export communities are often characterized by larger organisms that sink to depths where the carbon they contain is sequestered from the atmosphere. Zooplankton can enhance export by aggregating prey into larger sinking fecal pellets; however fecal pellet flux is a highly variable component of the biological carbon pump. Relating plankton trophic dynamics to changes in particulate carbon flux is an important step …

Biological, Behavioral And Preventative Management Of The Invasive Insect Pest, Spotted Wing Drosophila (Drosophila Suzukii Matsumura), In Maine Lowbush Blueberry (Vaccinium Angustifolium Aiton), Gabe Alnajjar

Electronic Theses and Dissertations

This research was conducted in order to identify the potential for utilization of various management techniques against the invasive Drosophila suzukii Matsumura, commonly referred to as the spotted wing drosophila (SWD), using Maine lowbush blueberry (Vaccinium angustifolium Aiton) as a model crop system. These included evaluations of three prospective approaches often considered when developing agricultural pest management programs for novel insect pests: 1) biological control through the intended release of natural enemies, in this case entomopathogenic fungi; 2) behavioral management through mass trap deployment in order to capture and kill adult SWD, and; 3) prevention through the deployment of …

Behavioral Ecology Of Landbird Migrants In A Complex And Changing Flyway System: The Gulf Of Maine, Adrienne J. Leppold

Electronic Theses and Dissertations

In and around the Gulf of Maine, over 300 species of birds have been documented during migration, and tens of millions of songbirds may pass through the region on a single autumn night. Shorelines are widely documented as major migration corridors. There is ample evidence that coastal areas concentrate migrants and many species make overwater movements to and from breeding and wintering grounds. Data collected from radar, banding, and ceilometry studies in the northeast have provided us with evidence that birds migrate along the coast and make overwater movements across the Gulf of Maine and Bay of Fundy during both …

Development Of Eco-Friendly Composite Foam Boards For Thermal Insulation And Packaging Purposes Using Cellulose Nanofibrils (Cnf), Nadir Yildirim

Electronic Theses and Dissertations

Reducing energy consumption is a high priority in the United States and throughout the world. Energy used to heat and cool occupied constructed facilities is of particular concern, and one of the most effective strategies is insulating the building envelope. Historically, builders used whatever material was available to fill the void between interior and exterior walls, including wool fibers, paper, and even corn cobs. Today, homes are built using foam insulation that harden when applied, blown-in loose insulation, fiberglass mats or rigid foam boards usually composed of polystyrene. Rigid foam boards are used in a variety of applications despite the …

Spruce Grouse Habitat Ecology In Maine's Commercially Managed Acadian Forest, Stephen W. Dunham

Electronic Theses and Dissertations

Spruce grouse (Falcipennis canadensis) inhabiting the mixed coniferous-deciduous forests of the northeastern United States are at the southern extent of their range. These mixed forests are known collectively as the Acadian forest and represent the transitional zone between the boreal forest to the north and the deciduous northern hardwoods forests to the south. Often assumed to be associated with mature, unharvested forest in this region, few studies have assessed habitat relationships of the species within areas dominated by commercial forest management. We investigated the influence of stand maturity, vertical and horizontal cover, and patchiness on the occupancy and …

Production Of Acetic Acid In Kraft Pulp Mill Biorefinery Using Bi-Polar Membrane Electrodialysis, Ravikant Amogisidha Patil

Electronic Theses and Dissertations

The objective of this dissertation was to develop a process for the production of acetic acid in kraft mills. Acetyl groups in hardwood can be hydrolyzed using alkali at 50 °C. The product from this process contains about 15 g/L of sodium acetate and was determined to be suitable for the production of acetic acid.

Experiments performed using aqueous sodium acetate to evaluate the ability of electrodialysis (ED) to separate and concentrate sodium acetate showed that sodium acetate can be concentrated up to 275 g/L starting with an initial concentration of 17 g/L. The transport of water with sodium and …

Exploring The Threats Of Dams And Ocean Conditions: In-River Movements And Ocean Growth Of Atlantic Salmon (Salmo Salar) From Maine's Rivers, Lisa K. Izzo

Electronic Theses and Dissertations

Substantial declines of anadromous Atlantic Salmon Salmo salar have occurred throughout the range of the species, with many populations at the southern extent of the distribution being extirpated or endangered. While Maine is the last state in the country where adult Atlantic Salmon return to rivers each year to spawn, numbers have decreased dramatically in recent decades, with typically less than 2,000 spawners returning to all Maine's rivers combined. The complex life history of this species, which involves a juvenile freshwater phase followed by a marine phase that can last one to five years before returning to freshwater to spawn …

Social And Ecological Factors Affecting The Adoption Of Aquaculture, Karen Pianka

Electronic Theses and Dissertations

Commercial fishermen in Maine are increasingly dependent upon the American lobster fishery, and this reliance on a single species poses a threat to working waterfronts. Aquaculture represents a potential opportunity for commercial fishermen to diversify their income. Literature on the adoption of innovation suggests that factors such as age, education level, fishing experience, diversification, and leadership are important predictors of early adoption of innovation. However, few studies have examined whether such factors affect the adoption of aquaculture by commercial fishermen. Our marine policy research studied fishermen enrolled in two pilot shellfish and seaweed aquaculture classes held in 2013 in Harpswell …

Assessment Of A Hatchery Based Rainbow Smelt Supplementation Effort, Andrew O'Malley

Electronic Theses and Dissertations

Rainbow Smelt (Osmerus mordax) are an important fish distributed throughout northeastern North America with both anadromous and landlocked populations. Abundance, size at age, and maximum size vary widely among populations and life histories. In order to compare anadromous and landlocked populations, we collected spawning adults in 2014 from four anadromous and three landlocked populations. Scales and otoliths from the anadromous fish were examined and compared for estimates of bias and precision in ageing. Analysis of both scales and otoliths provided age estimates that were acceptable, but estimates from scales were more precise and had less bias. Otoliths were …

Eating For Environmental And Personal Health: Green Eating, Health Behavior And Environmental Perceptions At The University Of Maine, Moira E. Burke

Electronic Theses and Dissertations

The purpose of this study was to determine if green eating (GE), defined as environmentally conscious eating, in college students had an impact on BMI, health behavior, fruit and vegetable intake, physical activity, and perceptions of the campus environment. This was a cross-sectional study of undergraduate and graduate students (n=190) at the University of Maine. The GE Survey was used to determine GE stage of change; participants were classified as either pre-action (precontemplation, contemplation, preparation) (n=113) or post-action (action, maintenance) (n=77). The GE Survey was also used to assess GE behavior, decisional balance, and self-efficacy. A de novo health behavior …