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Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, Val Watson

Electronic Theses and Dissertations

Ecological restoration is an increasingly common practice across ecosystems, and current practices aim to restore the biological and physical processes underlying ecosystem function, often for the sake of endangered higher-level consumers. Studies of restoration outcomes often report few or inconsistent ecological changes, and monitoring of restoration projects rarely measures ecological processes. Monitoring also usually measures outcomes at a single scale, despite the prevalence of scale- dependent phenomena across ecosystems. My thesis uses measurements of ecological processes to assess restoration response and evaluates responses across multiple scales. I focus here on a long-term large wood addition project on the Narraguagus River …

Browntail Moth (Euproctis Chrysorrhoea) Integrated Pest Management Program: Evaluation Of Monitoring Traps And Biopesticides, Sadia Crosby

Electronic Theses and Dissertations

Browntail Moth (BTM; Euproctis chrysorrhoea) is a non-native species currently outbreaking in Maine. BTM are polyphagous folivores and feed on a variety of woody plant species, including many economically and ecologically important ornamental and forest trees such as oaks and apples. Human health is also a concern as BTM larvae produce urticating hairs that can cause severe dermatitis in people. New monitoring and management programs are urgently needed, with the current population densities reaching a 100-year high.

The Maine Forest Service monitors BTM populations by visually assessing winter nest densities and defoliation patterns, both time and labor intensive. This …

Form And Risk Class Distribution And Its Effect On Estimated Product Ratios In Commercial Species Commonly Found In Northeastern Forests And A Comparative Analysis Of Contrasting Field Inventory Methodologies, Ryan Smith

Electronic Theses and Dissertations

Estimating product ratios in hardwood forests is difficult due to the highly complex stem forms and diverse growth and regeneration strategies found in hardwood species. This is of particular concern for landowners with large ownerships requiring robust product potential estimates as part of both short-term tactical harvest planning and long-term growth and yield projections. Hardwood-dominated forests are generally managed for high-value sawlog and veneer products. This makes it increasingly important to identify strategies for improving hardwood management to meet economic (maximizing sawlog recovery) and ecological (maintaining healthy and diverse forests) goals.

This study seeks to achieve two primary goals. The …

A Sky Island Perspective: New England Alpine Plant Distributions Across The Region, Andrea Tirrell

Electronic Theses and Dissertations

Alpine ecosystems around the globe are at risk due to climate change, human disturbance, and habitat loss. New England alpine zones are small and fragmented, which could make them vulnerable to global change. However, the persistence of tundra relics throughout the Holocene suggests the persistence of these communities in microclimate refugia. Assessing the near-term vulnerability of alpine plant communities is challenged by a lack of standardized, repeat surveys and long-term monitoring data, which presents a challenge for the many agencies monitoring New England’s alpine zones. Island biogeography theory predicts that alpine species richness is a function of area, but this …

Assessment Of Historical Climate Variability In Maine With Implications For Future Agricultural Productivity And Adaptation, Carly Frank

Electronic Theses and Dissertations

Climate change is a wicked problem with global impacts, one of which being the sustainability of the existing global food system. As temperatures and variability in precipitation are projected to increase, the challenges to agriculture are expected to intensify. This thesis examines the Maine historical climate record over the growing season, in combination with future projections, to assess how conditions have changed and will change with agricultural implications. In this analysis, relevant climatic variables are analyzed, and agriculture-significant measures are derived for Maine’s three climate divisions using four decades of daily and monthly gridded datasets. In addition, this thesis explores …

Functional Diversity In Blueberries And Their Responses To Extreme Drought, Pratima Pahadi

Electronic Theses and Dissertations

Climate change is expected to lead to novel climate conditions with an increase in frequency and severity of drought across many places around the globe including the north-eastern (NE) United States. Therefore, experimental studies that test the impacts of changing environmental conditions over long time scales or experimental studies that mimic these conditions are crucial to understand the potential impact on crops in this region. Wild lowbush blueberries and highbush blueberries are two important crops in NE USA. In this study, the leaf functional, structural, nutrient traits across genotypes of wild blueberries (Vaccinium angustifolium and V. myrtilloides) at …

Marine Aquaculture In Maine: Understanding Diverse Perspectives And Interactions At Multiple Scales, Melissa L. Britsch

Electronic Theses and Dissertations

Coastal oceans are changing and experiencing increased use. The social and ecological benefits of healthy coastal oceans are well documented and include habitats for marine species, storm protection, and recreational opportunities (MEA, 2005). As the impacts of human activities are recognized, questions about how ocean spaces should be used are becoming more common. These questions are complex and involve many tradeoffs. Understanding the values people hold about uses, and how activities and ecosystems overlap, is critical for weighing tradeoffs and improving future management. I use the northeastern U.S. state of Maine to study human interactions with coastal oceans. Maine is …

Holistic Monitoring Of Maine Sea Lice (Lepeoptheirus Salmonis, Kroyer, 1837) Sensitivities To Therapies: Developing A Novel Assay To Examine Lice Behavior, Kathryn Liberman

Electronic Theses and Dissertations

Sea lice (Lepeoptheirus salmonis) present significant economic and animal welfare challenges to salmon aquaculture globally. Chemical delousing agents are used in many countries, with each nation eventually reporting sea lice developing reduced sensitivities to treatments. While some countries have in place sea lice sensitivity monitoring programs, that is not the case in Maine, USA. Although chemical delousing agents are not currently used in Maine, they have been used in the past and are currently used in neighboring Canadian salmon farms. Different bay management areas (BMAs) were sampled during different seasons to determine if there is a seasonal or spatial component …

Consumer Acceptability Of Gulf Of Maine Sugar Kelp Seaweed In Baked Bread, Laurel Simone

Electronic Theses and Dissertations

Although steady interest in edible seaweed cultivation continues to grow in Maine, research is lacking regarding consumer preferences and purchasing behavior of seaweed-containing products. The purpose of this study was to determine consumer acceptability of seaweed baked bread and provide insights into purchasing behavior to reveal potential consumer groups that are most likely to buy and eat baked products containing seaweed. Consumer preferences were determined by a sensory evaluation test and an online survey.

Sixty-five participants completed the central location test of freshly-baked bread containing seaweed. Participants were required to be at least 18 years of age, willing to eat …

Examining The Northern Shrimp Fishery In A Changing Gulf Of Maine, Ashley N. Charleson

Electronic Theses and Dissertations

Northern Shrimp (Pandalus borealis) once supported a key commercial fishery in the State of Maine. Since its closure in 2013, the stock has remained in a particularly vulnerable state following recruitment failure, overfishing, and rising water temperatures. Furthermore, without this source of supplemental income, local fishermen have also experienced financial stress following unstable fishing conditions in other fisheries. The collective goal of this research project was to assess factors impacting the feasibility of reopening and maintaining this vulnerable winter fishery. These goals are addressed over 4 chapters. Chapter two offers insight regarding what is most often omitted from the regulatory …

Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias

Electronic Theses and Dissertations

Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi, which is transmitted through the bite of an infected blacklegged (deer) tick (Ixodes scapularis). Geographic invasion of I. scapularis in North America has been attributed to causes including 20th century reforestation and suburbanization, burgeoning populations of the white-tailed deer (Odocoileus virginianus) which is the primary reproductive host of I. scapularis, tick-associated non-native plant invasions, and climate change. Maine, USA, is a high Lyme disease incidence state, with a history of increasing I. scapularis abundance and northward range expansion. This thesis addresses the question: “To …

Broth: Enhancing Market Opportunities And Improving Sustainability Of Maine Farmed Seaweed, Zachary M. Bonelli

Electronic Theses and Dissertations

Seaweed is becoming popular across the world as consumers learn about the variety of seaweed-based products and their health benefits. Sugar kelp is one of Maine’s seaweed varieties that is locally grown each year. Sugar kelp and similar species contain many useful nutrients including iodine, calcium, magnesium, iron, and vitamins A, B, C, and E. Even though the health benefits of seaweed have been proven, locally-sourced seaweed has not yet become any more popular in Maine. Part one of this study identified suitable processing steps for a sugar kelp-based broth. Part two assessed how consumers’ demographics and food neophobia, as …

Propagation Of The Native North American Shrub Lonicera Villosa And Trait Comparisons With Nonnative Congeneric Taxa, Darren J. Hayes

Electronic Theses and Dissertations

The honeysuckles, or Lonicera, represent a circumboreally-distributed genus in the Caprifoliaceae family. A diverse assortment of vines, lianas, and shrubs comprise the genus, and honeysuckles have long been a staple of the horticultural industry, prized for their robustness as much as their sweet-scented flowers and colorful fruits. However, many cultivated honeysuckles of Eurasian origin have proven invasive outside of their native range, displacing native species and reducing overall diversity and ecosystem health. Planting of Eurasian Lonicera taxa is now often discouraged or banned throughout much of North America. Conversely, native North American Lonicera species are often sparsely distributed and …

Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis

Electronic Theses and Dissertations

Understanding population dynamics and how species interact with their environment are important components for conservation and management. Ruffed grouse (Bonasa umbellus) are a widely distributed and common game bird in North America and are a considered an important economic and cultural icon in Maine. Although they are a well-studied species, there has been little research focused on ruffed grouse population dynamics and habitat relationships in Maine. My thesis aims to improve this knowledge gap by focusing on research related to survival and harvest of ruffed grouse, as well as male ruffed grouse resource selection at breeding display sites. Ruffed grouse …

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 …

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 …

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. …

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 …

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

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

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 …

Sources Of Variability In Agronomic Weed Seed Predation: Time, Space, Habitat, And Hyperpredation, Sonja K. Birthisel

Electronic Theses and Dissertations

Weed seed predation is an ecosystem service that benefits farmers by decreasing seedbank inputs, thereby reducing weed pressure in subsequent growing seasons. Seed predation can be considerable, but is highly variable. Sources of variability may include time, space, habitat, and trophic interactions such as hyperpredation. Two experiments were conducted to measure the impacts of these sources of variability on weed seed predation rates in Maine mixed vegetable agroecosystems.

Chapter One of this thesis describes a series of landscape-level field experiments conducted to quantify the effects of time, space, and habitat on seed predation rates. Seed assays, with and without vertebrate …

Production Ecology And Stand Dynamics Of Young Acadian Forest Stands In Response To Silvicultural Intensity And Compositional Objectives, Andrew S. Nelson

Electronic Theses and Dissertations

Early successional stands are common across the Acadian forests of eastern Canada and the Northeastern US. However, productivity and dynamics of these stands, as well as the underlying mechanisms influencing these processes, under different management scenarios are poorly understood. To address this need, I used a factorial experiment that controlled silvicultural intensity and species composition to quantify the effects of varying treatments on early stand dynamics, and the physiological and morphological factors influencing tree performance . Specifically, I studied: 1) species differences in aboveground allometrics, 2) light capture, light-use efficiency (LUE; growth/light capture), and foliar carbon isotope composition (δ13C) of …

A Case Study Approach For Assessing Operational And Silvicultural Performance Of Whole-Tree Biomass Harvesting In Maine, Charles E. Coup

Electronic Theses and Dissertations

In the Northeastern United States, re-emerging markets for renewable energy are driving interest in increasing the harvest of underutilized biomass material from Maine’s forest. These markets may offer opportunities for forest managers to implement silvicultural treatments that have previously been foregone due to their high cost. However, many operational challenges arise in using current harvesting systems to harvest biomass material profitably while simultaneously achieving silvicultrual objectives. This research uses a case study approach to analyzing some of the possibilities and obstacles in implementing biomass harvesting in Maine. The first three studies investigate a factorial silvicultural and operational case study involving …

The Influences Of Conventional And Low Density Thinning On Leaf Area, Growth, And Growing Space Relationships Of Eastern White Pine (Pinus Strobus L.), Christopher Henry Guiterman

Electronic Theses and Dissertations

Despite the commercial importance and widespread management of eastern white pine {Pinus strobus L.) in the Northeast, surprisingly little is known about the effects of thinning on even-aged stand development. To address this, patterns of leaf area, bole form, volume growth, and growth efficiency - defined as volume increment per unit leaf area - were examined over a 17-year period within a thinning study in central Maine designed to compare the conventional B-line and low density thinning regimes. At the tree-level, many of the effects of thinning were as expected. Heavier, low density thinning resulted in significantly larger and deeper …

Effects Of Fish Introductions On The Geographic Distribution And Native Invertebrate Biodiversity Of Naturally Fishless Lakes In Maine, Emily Gaenzle Schilling

Electronic Theses and Dissertations

Widespread fish stocking has led to a worldwide decline in naturally fishless lakes and their associated communities. Little is known about the historical distribution or native communities of these freshwater ecosystems. The objectives of this study were to: 1) develop a quantitative method to remotely detect naturally fishless lakes in Maine, 2) conduct a landscape-scale assessment of unique attributes of fishless lake macroinvertebrate communities, 3) identify macroinvertebrate bioindicators of fish absence, and 4) assess effects of introduced fish on native macroinvertebrates. I identified two physiographic types of naturally fishless lakes in Maine: kettle lakes in the eastern lowlands and foothills …

The Effects Of Chronically Elevated N And S Deposition On The Nutrition And Physiology Of Sugar Maple At The Bear Brook Watershed In Maine, Suzanne Bethers

Electronic Theses and Dissertations

The Bear Brook Watershed in Maine is a paired watershed system; one watershed has been acidified bimonthly with granular ammonium sulfate ((NH₄)₂SO₄) since 1989. The adjacent watershed is used as a reference. This acid deposition treatment presents unique opportunities to look at the long term affects of acidification on vegetation. Acidic deposition continues to be a concern for the health of sugar maple (Acer saccharum Marsh.) in northern hardwood forests. Many studies show a connection between base cation depletion induced by acid deposition and sugar maple decline. In this text we …

State Of Maine Forester Licensure Program And Policy Review, Stephen F. Holt

Electronic Theses and Dissertations

Despite the continued importance of the forest resources to the State of Maine that led to the initial forester registration law in 1975, forester regulation has been the subject of only one program audit and policy review. That occurred 20 years ago, in 1986.

It is important to understand the need for a periodic forester regulatory program review even if there are no currently apparent or expected public interest or resource protection related issues.

There have been many significant changes since the last forester regulatory program and policy review that have impacted forest policy, management, and the related forestry based …

Revegetating Blackwoods Campground, Acadia National Park: Emphasis On Natural Regeneration Of Red Spruce And Balsam Fir, Cristin O'Brien

Electronic Theses and Dissertations

Blackwoods Campground in Acadia National Park has a declining vegetative understory, characterized by a lack of tree seedling recruitment and shrub populations. This project was embarked upon to identify limiting factors to tree seedling establishment and shrub survival. From these studies, management plans will be developed for revegetating the campground understory. To better understand the factors that inhibit successful seedling establishment, we investigated the effects of varying soil moisture levels on seed germination, seedling survival and seedling dry mass accumulation for red spruce and balsam fir. We also studied the effect of organic layer depth on seedling growth for both …

Population Dynamics And Spatial Analysis Of The Maine Green Sea Urchin (Strongylocentrotus Droebachiensis) Fishery, Robert C. Grabowski

Electronic Theses and Dissertations

Fisheries research on the green sea urchin in Maine has been limited despite its importance to the state's fishing industry. The objective of this thesis was to generate critical information for the management and monitoring of the Maine green sea urchin fishery. In particular there are three main areas of interest: (1) an investigation of biological reference points; (2) spatial analysis and biomass estimation, and (3) the development of a simulation framework approach to determine an optimal sampling strategy for the fishery-independent survey program. Biological reference points are markers conlrnonly used to monitor and manage fisheries. For the Maine sea …