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Forest Disturbance And Occupancy Patterns Of Carnivores: Results Of A Large-Scale Field Study In Maine, Usa, Bryn E. Evans Dec 2021

Forest Disturbance And Occupancy Patterns Of Carnivores: Results Of A Large-Scale Field Study In Maine, Usa, Bryn E. Evans

Electronic Theses and Dissertations

Understanding trends in the abundance and distribution of carnivores is important at global, regional and local scales due to their ecological role, their aesthetic and economic value, and the numerous threats to their populations. Carnivores in Maine range from the American black bear (Ursus americanus), to numerous native mesocarnivore species, such as American marten (Martes americana), fisher (Pekania pennanti), coyote (Canis latrans), red fox (Vulpes vulpes), bobcat (Lynx rufus), Canada lynx (Lynx canadensis) and to two small weasel species (Mustela erminea and Neogale frenata). …


Environmental Impacts On The Reproduction Of Three Cold-Water Corals, With Implications For Their Vulnerability To Ocean Warming And Climate Change, Julia Johnstone Aug 2021

Environmental Impacts On The Reproduction Of Three Cold-Water Corals, With Implications For Their Vulnerability To Ocean Warming And Climate Change, Julia Johnstone

Electronic Theses and Dissertations

Cold-water corals are important habitat builders in the deep ocean worldwide. Despite being known for centuries, recent technological advances and deep-sea exploration has revealed cold-water corals thriving at depths of up to 6000m. Similar to their warm-water relatives, cold-water corals are hotspots of diversity, with their structures creating habitat for thousands of associated species. Some cold-water corals create bioherms that stretch for tens of kilometers, while others come together to form vast undersea forests. These habitats are often home to commercially important fisheries species, and conservation efforts have recently begun to regulate fishing in cold-water coral ecosystems to protect them …


To Know The Land With Hands And Minds: Negotiating Agricultural Knowledge In Late-Nineteenth-Century New England And Westphalia, Justus Hillebrand Aug 2021

To Know The Land With Hands And Minds: Negotiating Agricultural Knowledge In Late-Nineteenth-Century New England And Westphalia, Justus Hillebrand

Electronic Theses and Dissertations

Ever since the eighteenth century, experts have tried to tell farmers how to farm. The agricultural enlightenment in Europe marked the beginning of a long arc of new experts aiming to change agricultural knowledge and practice. This dissertation analyzes the pivotal period in the late nineteenth and early twentieth century in Germany and the United States when scientists, improvers, and market agents began to develop comprehensive ways to communicate agricultural innovation to farmers. In a functional approach to analyzing the negotiation of agricultural knowledge through its communication in things, words, and practices, this dissertation argues that the process of change …


Expanding Our Understanding On Feed Spoilage And Developing Novel Approaches For Its Mitigation, Marjorie A. Killerby Aug 2021

Expanding Our Understanding On Feed Spoilage And Developing Novel Approaches For Its Mitigation, Marjorie A. Killerby

Electronic Theses and Dissertations

The main objective of this study is to improve the understanding and awareness of conserved feed spoilage and to develop novel technologies that can prevent it. In chapter 1, we conducted a meta-analysis to evaluate the effects of chemical (50 articles)and biological (21 articles)preservatives on hay spoilage during storage. Multi-level linear mixed-effects modelswere fit including moderators:Preservative Class (PC), forage type (FT); moisture class (MC), and application rate (AR). Dry matter (DM) loss was affected by PC×FT (P=0.045), PC×AR (P<0.001), and PC×MC (P=0.009),relative to the overall effect of preservatives (-0.37% units). DM loss in propionic acid (PropA)-treated hay was numerically reduced to a greater extent in grasses (-16.2), followed by mixed hay (-1.76), but it was actually increased (+2.2%)in legume hay.Increasing ARof PropA resulted in decrease in DM loss (β = -1.34).Application ofBuffered Organic Acids,Other Organic Acids, PropA,and Anhydrous Ammoniadecreased visual moldiness by -22.1, -29.4, -45.5 and -12.2% units, respectively (PC; P<0.001). Sugars increased in treated grass hay (+1.9) and decreased in treated legume hay -0.8% DM, respectively (P<0.001). Microbial inoculants had small effects on hay spoilage since the overall DM loss effect size was - 0.21%. Inoculated grass hay preserved moresugars (+1.47) than treated legume hay (+0.33) relative to untreated hay (x=4.63% DM; P<0.001). In conclusion, organic acid-based preservatives effectively prevent spoilage of hay as influenced by FT, MC and AR, but microbial inoculants had only small effects. In chapter 2, we evaluated the effects of chemical and biological preservatives and ensiling stage on spoilage, ruminal in vitro fermentation, and methane production of wet brewer’s grain (WBG) silage. Treatments (TRT) were sodium lignosulfonate at10 g/kg (NaL1) and 20 g/kg (NaL2; fresh WBG), propionic acid at 5 g/kg fresh WBG (PRP, 99%), a combination inoculant (INO; Lactococcus lactisand Lactobacillus buchneri each at 4.9 log cfu/fresh WBG g), and untreated (CON). Three stages (STG) were tested:treated WBG (Fresh) was ensiled for 60 d(Ensiled), after which they were opened and aerobically exposed for 10 d (AES). Data were analyzed as a RCBD (5 blocks) with a 5 TRT × 3 STG(Fresh, Ensiled and AES) factorial arrangement. Our results show that Ensiled PRP-treated WBG markedly preserved more sugars (250) and starch (190) than all other Ensiled TRT (x=136 ± 16.2sugarsg/kg DM and x=121 ± 6.15 starch g/kg DM, respectively; P<0.001). Due to its superior nutritive value, PRP-treated AES was less aerobically stable than CON (61.9 vs. 90.1 h; P = 0.03). Preservation was not improved by INO, NaL1 or NaL2, but the latter prevented the increase of neutral detergent fiber (NDF)across STG (x=384).In vitro ruminal fermentation of Fresh WBG resulted in higher methane concentration (0.94) and yield (0.27) than theother STG (x=0.84 ± 0.07mMand x=0.23 ± 0.03mmol/g fermented OM, respectively). In conclusion, PRP was the most effective at preserving WBG during ensiling but failed to improve aerobic stability. In chapter 3, we evaluated the effects of application rate (AR) of sodium lignosulfonate (NaL) and propionic acid(PRP)on high moisture alfalfa hay spoilage during storage and its nutritive value. Treatments (TRT; NaL and PRP) were applied at four AR: 0 (CON), 2.5, 5 and 10 g/kg (fresh basis) to alfalfa hay at 68.5% DM, packed into mini balesand stored for 33 d.Data were analyzed as a RCBD(5 blocks) with a 2 TRT x 4 AR factorial arrangement. At d 33, DM losses were decreased by PRP at 5 and 10 g/kg (0.9), vs.CON (6.92) andNaL (6.63 ± 1.13%). Visual moldiness (0-10) and mold counts were also decreased by PRP at 5 (2.4 and 5.30) and 10 g/kg (0 and 2.7) relative to CON (6.0 and 7.13) and NaL (5.85 ± 0.67 and 7.21 ± 0.31 log cfu/fresh g, respectively). Both TRT increased apparent in vitroDM digestibility at all AR relative to CON (x=543 vs 501 ± 12.0g/kgof DM, respectively), but the acetate-to-propionate ratio was higher for NaL at 10 g/kg (3.02) vs. CON (2.89 ± 0.04). In conclusion, NaL failed to prevent spoilage of high moisture alfalfa hay while PRP was effective at doses >5 g/kg. Both TRT at 10 g/kg improved the rumen in vitro fermentation measures of high moisture alfalfa hay but PRP …


The Impacts Of Embryonic Arsenic Exposure Of Fundulus Heteroclitus, Torey Bowser Aug 2021

The Impacts Of Embryonic Arsenic Exposure Of Fundulus Heteroclitus, Torey Bowser

Electronic Theses and Dissertations

Arsenic is a toxic metalloid that exceeds safe drinking water standards in groundwater in many locations worldwide. Arsenic exposure in fish has been linked to destruction of gill tissues, impairment of growth, decreased muscle mass, memory impairment, increased aggression, and avoidance behaviors. We examined the behavior of mummichogs (Fundulus heteroclitus) following arsenic exposure during development in two studies. Embryos were collected from fish from three reference sites: Scorton Creek (SC), Massachusetts, Wells Harbor (WE), Maine, and Block Island (BLOC), Rhode Island and two contaminated sites: Callahan Mine (CM), Brooksville, Maine, and New Bedford Harbor (NBH), Massachusetts. Embryos were …


The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang Aug 2021

The Impacts Of Climate Change On The Gulf Of Maine Northern Shrimp (Pandalus Borealis) Distribution, Reproduction, And Life, Hsiao-Yun Chang

Electronic Theses and Dissertations

The Gulf of Maine northern shrimp (Pandalus borealis) once supported a significant winter fishery for the Gulf of Maine (GOM). Although the shrimp fishery is not comparable to the lobster business, it provided fishermen and many coastal communities jobs and incomes in winters after lobster seasons. However, a moratorium has been put on the shrimp fishery since 2014 due to record low population abundance and perceived recruitment failures. The recruitment failures have been correlated with warming water temperatures over the past decade. The GOM has been recognized as experiencing rapid warming as a result of global climate change. …


Moving Towards The Science-Based Fisheries Management (Sbfm) In China, Shu Su Jul 2021

Moving Towards The Science-Based Fisheries Management (Sbfm) In China, Shu Su

Electronic Theses and Dissertations

Sustainable fisheries management requires decisions to be made based on sound science. To help ensure this, a Science-Based Fisheries Management (SBFM) system should be established to produce the best available science (BAS) and to ensure that the BAS forms the basis of decision-making. The goal of this dissertation is to look at how China, the world’s largest marine fisheries country, might build an effective SBFM system to enable its marine fisheries to attain sustainability. Studies were conducted to answer the following guiding questions: 1) what is SBFM? 2) why is it necessary for China to deploy SBFM? 3) what are …


The Human Dimensions Of Aquaculture Development In Maine Including A Governance Perspective, Molly Frances Miller May 2021

The Human Dimensions Of Aquaculture Development In Maine Including A Governance Perspective, Molly Frances Miller

Electronic Theses and Dissertations

Aquaculture is the fastest growing food production system in the world. Aquaculture growth is heavily influenced by the governance system that establishes property rights and determines the rules by which individuals and communities must follow. This dissertation focuses on the social and ecological factors that influence development of marine aquaculture, as they exist within the governance system, in Maine, USA. In Maine, the marine aquaculture industry is experiencing a period of intense growth necessitating further understanding of the factors shaping its development. Chapter 2 analyzes semi-structured key informant interviews to identify challenges and opportunities to inform sustainable industry growth. Research …


The Effect Of Bts Induced Inactivity On A Zebrafish Model Of Duchenne Muscular Dystrophy, Sean Driscoll May 2021

The Effect Of Bts Induced Inactivity On A Zebrafish Model Of Duchenne Muscular Dystrophy, Sean Driscoll

Electronic Theses and Dissertations

Duchenne’s Muscular dystrophy (DMD) is a congenital disease of the muscle characterized by muscle atrophy, weakness, and a lower quality of life. Often diagnosed in children, it affects about 1 in every 5,500-7,700 males. A patient diagnosed with DMD is often told to avoid physical activities outside the required amount needed to go on with their day in order to preserve the muscle fibers and integrity. Inactivity in a healthy person leads to decreased muscle mass and increased weakening of the muscle, so we questioned if the effects may be exacerbated in a person diagnosed with DMD having already weakened …


Evaluating And Advancing Opportunities For Ecosystem Services, Increased Production, And Sustainability Of Kelp Aquaculture In The Gulf Of Maine, Gretchen Schott Grebe May 2021

Evaluating And Advancing Opportunities For Ecosystem Services, Increased Production, And Sustainability Of Kelp Aquaculture In The Gulf Of Maine, Gretchen Schott Grebe

Electronic Theses and Dissertations

Commercial seaweed farming efforts are expanding worldwide. The use of new species, ecosystems, and practices present many opportunities for novel research and resource management. The purpose of this project was to evaluate and advance seaweed aquaculture practices in the Western Gulf of Maine. Saccharina latissima (sugar kelp) is the species of focus because it is currently the most farmed macroalga in the Northeastern United States. Fieldwork supporting the empirical studies was conducted January 2016 - May 2019 in Casco and Saco Bays, ME. Growth, yield, morphology, elemental and isotopic composition, and enzymatic activity of S. latissima were quantified across four …


Dietary Change Among Canis Familiaris During The Late Ceramic Period On The Maine-Maritime Peninsula: A Case Study From The Holmes Point West Site (Me 62-8), Machias Bay, Maine, Abby E. Mann May 2021

Dietary Change Among Canis Familiaris During The Late Ceramic Period On The Maine-Maritime Peninsula: A Case Study From The Holmes Point West Site (Me 62-8), Machias Bay, Maine, Abby E. Mann

Electronic Theses and Dissertations

Archaeological study of Indigenous pasts has been characterized by a focus on objects over people. This study attempts to humanize the past by illuminating human agency in the human-dog relationship through a case study of dog health and diet during the Late Ceramic period (ca. 950 – 450 BP) in the Maine-Maritime Peninsula region. To circumvent the cycle of western knowledge building and marginalization of Indigenous communities, past Wabanaki people and their relationships with dogs are positioned at the center of research questions presented here. Few studies in the Northeast have analyzed dog remains from the Ceramic period (ca. 3050 …


A Bioeconomic Analysis Of Sea Scallop (Placopecten Magellanicus) Aquaculture In The Gulf Of Maine, Struan Coleman May 2021

A Bioeconomic Analysis Of Sea Scallop (Placopecten Magellanicus) Aquaculture In The Gulf Of Maine, Struan Coleman

Electronic Theses and Dissertations

Aquaculture is the fastest growing food production sector in the world. In the Northwest Atlantic, interest in Sea Scallop (Placopecten magellanicus) (hereafter scallop) aquaculture has grown rapidly in the last decade. In the U.S., scallops support a ~$1 billion USD industry with nearly $500 million coming from imports. By comparison, the U.S. exports only ~$139 million USD of scallops annually. This substantial trade imbalance and strong domestic demand has created an opportunity for a farmed product to capture a share of the market. However, technical, regulatory, and, perhaps most importantly, economic challenges have stifled the growth of scallop aquaculture in …