Life Sciences Commons^™

Developing A Collaborative Research Program To Evaluate Fine-Scale Groundfish Dynamics In Eastern Maine, Mattie Rodrigue

Electronic Theses and Dissertations

Fisheries science conducted and used for management strategies in the Gulf of Maine (GOM) is conducted at broad spatial and temporal scales. There is a tendency for fisheries-independent monitoring programs, which play a critical role in fisheries assessment and management, to miss fine-scale dynamics, especially given the complex hydrographic structures characterizing the GOM. In New England, fishermen participating in a heterogeneous groundfish fishery within the GOM may have varied perceptions of fish abundance or distribution depending on the scale at which they participate in the fishery. Overlooking fine-scale life-history dynamics coupled with scale-mismatch in science and management may perpetuate a …

Light Dynamics In The Damariscotta River Estuary With Implications For Microphytobenthos, Teiga C. Martin

Honors College

Predicting benthic light fields in the Damariscotta River Estuary (DRE) allows us to evaluate optimal microphytobenthos habitat, and determine the most the productive regions of the DRE. A model was created using instantaneous photosynthetically active radiation (PAR) to predict the spatial distribution of sufficient light fields for primary production along the benthos of the estuary. PAR was collected at six stations oriented N- S along the DRE during late September in 2016 and 2017. Calculated at each station was Z1%, experimental and model diffuse coefficients of light (Kd), and the optimal light level depth for microphytobenthos production. Light fields were …

Maine Epscor Fall 2017 Newsletter, Maine Epscor

General University of Maine Publications

National Science Foundation (NSF) advances excellence in science and engineering research and education in Maine. Two NSF EPSCoR grants are currently underway in our state, and I’d like to take this opportunity to highlight some of our recent achievements.

SEANET consists of 42 faculty members, 90 undergraduate students, 43 graduate students, and 3 Ph.D. candidates, who are engaged in aquaculture research at 11 institutions across the state. Recent accomplishments include:
• Successful National Science Foundation (NSF) site visit completed in August 2017, which reviewed the project against plans and objectives
• SEANET faculty and students have been highly productive, with …

Improving Management And Conservation Of Cusk (Brosme Brosme): Habitat Distribution, Bycatch Interactions, And Conservation Practices, Jocelyn M. Runnebaum

Electronic Theses and Dissertations

Cusk (Brosme brosme) are a National Oceanic and Atmospheric Administration species of concern, currently under internal status review for the Endangered Species Act, but are considered data limited. Current concerns for cusk include: decline in abundance, increase in fishing mortality relative to survey biomass, increased patchiness in habitat, and lack of management (72 FR 10710). Future management will require an improved understanding of cusk distribution, habitat use, spatial distribution of bycatch interactions, and the impact of bycatch on the population. This study set out to evaluate changes in cusk distribution and habitat, locations and levels of bycatch, and …

Lobster In A Changing Gulf Of Maine: Investigating The Temporal Impact On Molting And The Fishing Fleet, Kevin W. Staples

Electronic Theses and Dissertations

We investigated the phenological and fisheries dynamics surrounding the spring molt of American lobster (Homarus americanus, Milne Edwards 1847) in the Gulf of Maine. We created a time series from Maine Department of Marine Resources Lobster Sea Sampling data using logistic models to estimate the timing and duration of the spring molt for eastern, central, and western regions of the Maine coast. These estimates revealed substantial inter-annual variability in the timing of the spring molt for all regions and that 2012 was indeed anomalously early relative to other years. Each region experienced significantly different molt timing for any given …

Investigating Factors Contributing To Reduced Embryo Survival In Farm Raised Atlantic Salmon, Salmo Salar L., Leeanne Thayer

Electronic Theses and Dissertations

Embryo mortality of Atlantic salmon, Salmo salar Linnaeus 1758, has been increasing for more than a decade in the State of Maine, a leading producer of this species in the United States. Increasing embryo mortality not only creates a financial bottleneck for farms but also prevents the sale of surplus eggs as an additional source of revenue. Blood and egg samples were collected at three Maine Atlantic salmon farms from female broodstock at the time of spawning over a 2-year period. Correlative factors for reduced embryo survival were investigated by measuring egg and maternal plasma concentrations of 17-estradiol (E2), 11-ketotestosterone …

Notes On Contributors

The Catch

No abstract provided.

The Mackerel Fishermen, Avery B. Stone

The Catch

No abstract provided.

Cormorant, Judy Kaber

The Catch

No abstract provided.

Awakening, Angela M. Waldron

The Catch

No abstract provided.

Editor's Note, Leonore Hildebrandt

The Catch

No abstract provided.

Full Issue Volume V

The Catch

No abstract provided.

Population Ecology Of Colonially Breeding Seabirds: How Intrinsic Processes, Mediating Influences, And Individual Heterogeneity Affect Population Vital Rates, Aly Mcknight

Electronic Theses and Dissertations

Seabirds have great potential to serve as marine indicators. However, before we can interpret seabird trends with confidence, we need a better understanding of the role of intrinsic processes, mediating influences, and lifetime experience in modulating relationships between prey availability and seabird population dynamics.

Intrinsic processes, mediating influences, and seabird productivity. I assessed productivity (chicks per breeding attempt) at Black-legged Kittiwake (Rissa tridactyla) colonies in Prince William Sound, AK and managed Common Tern (Sterna hirundo) colonies in the Gulf of Maine. Both systems showed evidence of intrinsic control; factors mediating access to prey were also important.

Mediating influences, individual heterogeneity, …

Divergent Responses Of Larval And Juvenile Blue Mussels To Low Salinity Exposure, Melissa A. May

Electronic Theses and Dissertations

In this study, we compared the osmotic stress response of larval and juvenile blue mussels (Mytilus edulis) at the transcriptomic, metabolomic, and whole organism levels. Blue mussels inhabit coastal areas, where they face climate-induced reductions in nearshore salinity. Despite their ecological and economic importance, scientists do not fully understand the underlying transcriptomic and cellular mechanisms of the osmotic stress response in blue mussels or how the ability to respond to stress changes throughout development. Blue mussels spend the first weeks of life developing through several larval stages in the plankton. These early life history stages are more vulnerable …

Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer

Electronic Theses and Dissertations

Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …

Advancing Development Of Porphyra Umbilicalis As A Red Algal Model System And Aquaculture Crop, Charlotte Royer

Electronic Theses and Dissertations

The marine red alga Porphyra umbilicalis (Rhodophyta, Bangiaceae) has ideal traits to allow it to become a model organism, including its economic value, reproduction in the northwestern Atlantic through asexual neutral spores (NS), and availability of fully-sequenced nuclear and organelle genomes. Research on the bacterial component of the Porphyra microbiome is ongoing. To advance model organism development and support microbial studies, data on natural reproductive trends and early embryonic development are needed, along with a system for genetic transformation, and ways of visualizing the attached microbial community. To meet these needs, two years of phenological data were analyzed, revealing seasonal …

Age Structure Response Of Principal Groundfish To Marine Protected Areas In New England, Julian Chawarski

Electronic Theses and Dissertations

Atlantic cod (Gadus morhua), yellowtail flounder (Limanda ferruginea), and haddock (Melanogrammus aeglefinnus) were once dominant species in the New England fisheries economy, together accounting for over half of the landings value of groundfish. Over the last several decades, all three species have experienced dramatic shifts in spawning stock biomass (SSB) with current estimates for cod stocks at 3% and 7% of target biomass (Gulf of Maine and Georges Bank stocks, respectively), a strong contrast to haddock stocks that are nearly fully recovered (NEFSC 2014, 2017). As principally demersal species, they are easily targeted by …

The Potential Impact Of Climate Change On Blue Whale Migration In The Eastern Pacific, Amanda Shuman

Honors College

Climate change is one of the most pressing problems the world is facing today. Due to human emissions, the amount of greenhouse gasses in the atmosphere is escalating at a concerning rate. This increase is causing ocean temperatures to rise, pH levels to lower, and altering the habitats of countless species. Balaenoptera musculus, or the blue whale, is a highly migratory species that relies on the stability of its’ habitats for foraging and calving grounds. They rely on the upwelling of nutrients and consistent conditions that allow for substantial prey populations to accumulate. With the effects of climate change altering …

Art And Science: A Case Study Of Their Interconnectedness In The Marine Natural Sciences, Julia Mackin-Mclaughlin

Honors College

Science and art are interrelated in the form of scientific illustration: the act of observing a subject and translating the gained knowledge into a visual form. Humans have found inspiration from the natural world since our beginnings, but the practice of accurately portraying it arose with the growing interest in natural science in the 15th century. This paper explores three questions: what is scientific illustration, what is its role in scientific research, and how has it changed through history? Modern scientific illustration thrives as an effective method to teach the general public environmental issues. I present a case study using …

Ecosystem Metabolism Modeling Of Estuaries In Maine: Using Dissolved Oxygen As A Tool For Aquaculture Site Assessment, Katherine Miller

Honors College

The net primary productivity (NPP), also known as the net ecosystem metabolism, of an estuary is a value indicative of the growth and activity of an estuary’s primary producers, relative to the metabolic activity of its consumers. When NPP is high, estuaries exhibit autotrophic conditions that have the capacity to support fruitful bivalve aquaculture. For oyster farmers, the ability to monitor an estuary’s NPP would allow them to predict and prepare for seasonal changes to oyster growth that result from changes to their phytoplankton food source and access to dissolved oxygen (DO). Not only would this aid farmers on site …

The Effects Of Dioxin Exposure On The Hepatic Development Of Larval Shortnose Sturgeon (Acipenser Brevirostrum), Kelsey Moon

Honors College

Exposure to environmental pollutants is considered to be detrimental to the larval development of various fish species. The liver is thought to be a target organ for many chemicals because of its high lipid content which bioaccumulates lipophilic contaminants. Common impacts of dioxins found in fish livers include lipidosis and glycogen depletion. However, very few studies have been conducted to show these developmental issues in the early stages of long-lived species such as sturgeon. Given their bottom dwelling nature, sturgeon are more vulnerable to environmental pollutants such as dioxin which have long half-lives in aquatic sediments. This study sought to …

A Summary Of Landings, Legislative Actions, And Possible Climate-Induced Distribution Shifts In New England Fisheries, Dylan Trueblood

Honors College

New England’s fisheries produce millions of dollars annually, and monitoring and protecting these fisheries ensures the region’s prosperity. There is evidence that the distributional centers of many fish species are shifting north so they remain within their optimal thermal range. Twenty species in New England’s fisheries have been identified as being vulnerable to climate change and, for each of these species, landings data from New England and the Mid-Atlantic were analyzed for the years 1976 – 2015. Trends in landings data were compared to trends in temperature anomaly data. Major legislative events that may have impacted landings data, e.g., fishery …

Implications Of Body Size And Habitat Distribution Of Carcinus Maenas For Predation On Mytilus Edulis In The Gulf Of Maine, Mckenzie Thompson

Honors College

The blue mussel, Mytilus edulis, is a commercially important species along the Gulf of Maine. Its rapid decline in population size over the last forty years has led many researchers to question if the invasive green crab, Carcinus maenas, is affecting its distribution. The increase in annual mean water temperature, due to global climate change, has led many to fear an expansion of the green crab’s range and an increase in population density among areas they currently inhabit. The Damariscotta River in Walpole, Maine offers a unique thermal gradient to study the effects of temperature on green crab distribution, abundance, …

A Recommendation For Polyculture Agriculture To Reduce Nitrogen Loading That Leads To Hypoxia, Bethany Stevens

Honors College

The natural cycle of nitrogen is an essential part of both plant growth and crop

production, but in recent years there has been an increase in nitrogen through the use of synthetic fertilizers. Agricultural surface runoff can carry away the converted, mobile nitrate nitrogen into downstream systems leading to an unnatural influx of nitrogen. This increased nutrient load can stimulate algal growth in the marine ecosystem which can cause an oxygen depletion. When the dissolved oxygen levels fall, the area is deemed ‘hypoxic’ and can no longer support most aquatic life. In recent decades, industrial agriculture has used monoculture practices, …

Pathobiology Of Water Molds In Fish: An Insight Into Saprolegniasis, Kathryn Liberman

Honors College

Saprolegnia is an aquatic pathogen with a fishy appetite—it develops on farmed and wild fish populations as a notoriously destructive ‘water mold’. The etiologic agent of Saprolegniasis, Saprolegnia is an opportunistic oomycete that is of significant interest in the aquaculture industry due to its financial impact and widespread effect. Previously, infection models studying the effects of Saprolegnia utilized methods that were injurious to fish and did not mimic a natural outbreak, thus making it difficult to use to evaluate new treatments for the disease. By developing a novel zebrafish (D. rerio) egg infection model, a new insight into the pathogenesis …

Identifying Genes Essential For Lysogeny In Cluster E Mycobacteriophage Ukulele, Robert Levi Soohey

Honors College

Mycobacteriophage are viruses that infect Mycobacterium, including nonpathogenic M. smegmatis and pathogenic M. tuberculosis (1). Their genomes are diverse and the majority of their genes have no known function (1). Mycobacteriophage Ukulele was isolated from soil in Old Orchard Beach, Maine. Ukulele is temperate, carrying out both lysogenic and lytic lifestyles (8). Temperate phage typically encode integrase, excise, and repressor proteins, which regulate the change from lysogenic to lytic growth (10). Ukulele gp49 has been identified as the integrase but repressor and excise proteins have not been identified (8). Ukulele gp52 was previously proposed as a candidate repressor, predicted to …

Maine Epscor Spring 2017 Newsletter, Maine Epscor

General University of Maine Publications

National Science Foundation (NSF) EPSCoR Advances Excellence in science and engineering research and education in Maine. Three NSF EPSCoR grants are currently underway in our state, and I’d like to take this opportunity to highlight each of the three programs.

Our current NSF EPSCoR RII Track 1 grant, the Sustainable Ecological Aquaculture Network (SEANET), consists of four research themes (Ecological and Sociological Carrying Capacity; Aquaculture in a Changing Ecosystem; Innovations in Aquaculture; and Human Dimensions) that are collaborating through a variety of projects to positively impact Maine’s working waterfront. SEANET consists of 42 faculty members, 78 undergraduate students and 39 …

Best Practices For Healthy Beaches And Watersheds In Maine: Potential Bioremediation Strategies For Improving Water Quality, Elyse Defranco

Maine Sea Grant Publications

Maine’s watersheds face many challenges from human inputs, with pollution threatening the health of our beaches, rivers, and aquaculture operations. Maine’s rural communities often lack the resources to update aging sewer infrastructure or to adequately maintain septic systems, and these sources of pollution impact watershed health. In addition to addressing sources of pollution, which can be difficult to ascertain and challenging to address when located, bioremediation practices have the potential to aid in clean-up efforts. New technological advances and research discoveries in creative forms of bioremediation are being developed and are producing promising case studies around the world. These new …