Life Sciences Commons^™

Predicting Marine Teleost Responses To Ocean Warming And Pollution, Akila Harishchandra

Electronic Theses and Dissertations

Ocean warming and pollution are two detrimental anthropogenic factors causing rapid marine ecosystem degradation recorded in the past decades. These factors alter the marine environment intolerable for many marine species, forcing them to either adapt or shift their contemporary habitat ranges to reduce the extinction risk embedded with environmental degradation. Estimating marine species’ habitat range shifts, and their potential for developing adaptive mechanisms are critical for ecosystem conservation and management, human health risk assessment, and climate change vulnerability assessments. Given that, for the first chapter of this thesis, we focused on developing a species distribution model (SDM) integrating marine species …

Biophysical Factors Impacting Sea Lice Settlement And Survival, Eleanor R. Glahn

Electronic Theses and Dissertations

Atlantic salmon (Salmo salar L.) aquaculture production in Maine is a valuable contributor to the economy, the expansion of which has been challenged by the parasitic salmon louse Lepeophtheirus salmonis. As planktonic organisms, the life of the salmon louse is primarily dictated by the physical conditions of the environment: the temperature for development time, salinity for survival, and current velocity for transport. Salmon lice are obligate parasites for whom the successful infection of a suitable host is critical to completion of their life cycle. However, little is understood about the effects of current velocity on infection success. Hydrodynamic …

Optimizing Strategies To Hydraulically Plant Atlantic Salmon Eggs Based On Fry Dispersal Patterns, Ernest J. Atkinson

Electronic Theses and Dissertations

The Gulf of Maine Distinct Population Segment of Atlantic Salmon has suffered from habitat loss and exploitation over the last century. Hatchery supplementation has prevented the extirpation of the species, but stocking methods represent tradeoffs between survival, domestication, and logistics. Egg planting, the use of eyed embryos, maximizes natural rearing opportunities which can be important for adaptation. This method, however, is logistically demanding and requires significant labor over large spatial, but short temporal, scales dictated by the ontogeny of the fish. However, the survival and dispersal behavior of Atlantic Salmon fry immediately after emergence from eggs planted in artificial nests …

Climate Change And An Evolving Fishery: Do Declining Maternal Size And Planktonic Foods Affect Lobster Larval Survival In The Gulf Of Maine?, Alexander J. Ascher

Electronic Theses and Dissertations

Many marine organisms exhibit bipartite life-cycles whereby reproductive adults dwell on the benthos while the larvae are pelagic. The pelagic stage is subject to mortality rates which far exceed those experienced by the organism during its benthic existence. The larval phase therefore represents an important bottleneck to larval recruitment. Small changes to survivorship in the plankton can have large consequences for subsequent year-class strength. Understanding the factors influencing successful larval recruitment is an important step towards predicting future stock abundances and maintaining healthy fisheries. The American lobster (Homarus americanus) is a large benthic crustacean which is economically and culturally important …

Ontogeny Of Size-Specific Prey Selection And Handling Behavior Of Larval Lobster (Homarus Americanus), Evelyn M. Layland

Electronic Theses and Dissertations

The American lobster (Homarus americanus) plays an integral role in the coastal Northwest Atlantic as a benthic consumer and the target of the most valuable single-species fishery in North America. In the past decade, benthic recruitment of juvenile lobster has declined, even as egg production has increased, suggesting heightening levels of larval mortality. Recent correlative studies in the Gulf of Maine further suggest early stage larval survival may be related to the supply and composition of planktonic foods. Despite these correlative studies and the economic importance of the species, relatively little is yet known about how larval lobster …

Strategies To Promote Value And Resilience In The American Lobster (Homarus Americanus) Industry, Nicole Orminski

Electronic Theses and Dissertations

The American lobster (Homarus americanus) fishery is the most valuable single-species fishery in the United States and Canada (DFO, 2021; NOAA Fisheries, n.d.). Coastal communities on both sides of the border rely on the American lobster supply chain, which economically links the two countries with one another and with other countries around the globe. Ongoing disruptions (or shocks) threaten the functionality of the supply chain, and increased globalization leads to greater exposure to shocks as they are transmitted between systems. One research study described in this thesis aims to add value to the industry via post-harvest treatment of …

Understanding The Impacts Of Anthropogenic Effects An Habitat Variability Interactions On Maine's Rocky Intertidal Ecosystem, Laura Braun

Electronic Theses and Dissertations

The rocky intertidal ecosystem is an important ecological and cultural aspect of the picturesque Maine coast, playing a vital role in not only Maine’s coastal ecosystem, but also to Maine’s economy. It’s distinct community structure along the sharp elevational gradient and the presence of daily stressors (wave action, heat, and desiccation), make the rocky intertidal ecosystem an important model ecosystem to monitor for effects from anthropogenic impacts. In this thesis, I describe attempts to monitor and understand the impacts of two of these anthropogenic impacts on this system: climate change and industrial harvesting of Ascophyllum nodosum along Maine’s coast. For …

Using Reflex Actions To Predict Delayed Post-Harvest Mortality Of American Lobster (Homarus Americanus) In Maine’S Lobster Supply Chain, Cassandra Leeman

Electronic Theses and Dissertations

In live seafood industries, maintaining product quality and survivorship are critical aspects of the supply chain infrastructure. Post-harvest mortality in the American lobster (Homarus americanus) fishery can result in a significant loss in revenue for the largest single species fishery in North America. In Maine, the wholesale lobster distribution supply chain directly and indirectly supports state and local economies, providing almost $1 billion in revenue and dominates the fishery, producing 82% of the total lobster landings in the USA (Donihue, 2018; NOAA, 2021). However, at least 2% of the lobster landed in Maine die before they reach consumers, representing an …

Remotely Sensed Assessment Of The Preferred Habitat Of Alexandrium Catenella In The Gulf Of Maine And The Bay Of Fundy, Andre F. Bucci

Electronic Theses and Dissertations

Harmful Algal Blooms (HABs) of the toxic dinoflagellate Alexandrium catenella are an annually recurring problem in the Gulf of Maine (GoM), resulting in risks to human health and substantial economic losses due to shellfish harvesting closures. The monitoring approaches in the region are restricted to real-time identification of the HABs events, when they are clearly underway and already causing deleterious effects to the environment. To fully function as an early warning system rather than an immediate response, monitoring strategies need to be focused on environmental conditions preceding A. catenella HABs. However, the current understanding of the preferred habitat for A. …

Modeling Life History And Population Dynamics Of American Lobster And Atlantic Sea Scallops In A Warming Gulf Of Maine, Cameron T. Hodgdon

Electronic Theses and Dissertations

Climate change is impacting many marine species distributions, life histories, and behaviors, as well as their associated fisheries and overall production. This is perhaps especially true for the Gulf of Maine (GOM). Here, warming rates are exceeding a vast majority of the world’s oceans. This highly dynamic system supports myriad species, but is both economically recognized and culturally known for its Atlantic sea scallop (Placopecten magellanicus) and American lobster (Homarus americanus) fisheries. This dissertation examines the influence of regional climate change on these species in an effort to predict how these stocks and their fisheries may …

Age, Growth, Foraging, And Trophic Ecology Of Bigeye (Thunnus Obesus) And Yellowfin (Thunnus Albacares) Tuna In Continental Shelf And Slope Regions Of The Northeast U.S., Riley S. Austin

Electronic Theses and Dissertations

Traditional stock assessments require, in part, accurate knowledge of growth relationships to estimate a variety of aspects involved in population conservation management of exploited species. In addition, the local distribution and condition of top pelagic predators is driven by detection of abundant forage aggregations and along with traditional stock assessments, should be considered for effective management of marine populations. Empirical analyses of these data are severely lacking for bigeye (Thunnus obesus) and yellowfin (Thunnus albacares) tuna in the Atlantic Ocean, especially for the former. Given historical studies’ observations of these two top predators use as biological samplers due to their …

Linking Local Knowledge & Community Science In Support Of Coastal Marine Stewardship, Sarah Risley

Electronic Theses and Dissertations

In the last two decades, there has been a shift towards more integrated, ecosystem-based approaches to marine management, including fisheries. At the same time, there have been calls for greater inclusion of diverse perspectives in conservation science and practice. For these reasons, there is renewed interest in the integration of indigenous and local knowledge into science, management, and environmental decision making. Despite these developments, local knowledge often is poorly integrated or treated as something of lesser value than knowledge generated or curated by professional researchers. Novel methods that integrate social and ecological data and prioritize local knowledge and community-based approaches …

Use Of The New England Aquarium To Evaluate Environmental Dna Metabarcoding Of Gulf Of Maine Vertebrates And Invertebrates, Samantha Silverbrand

Electronic Theses and Dissertations

Environmental DNA (eDNA) metabarcoding is a tool that has been used to characterize biodiversity in a range of diverse systems. However, blind application of eDNA metabarcoding primer sets to new regions and species pools can result in poor taxon coverage and unaccounted detection biases. For the Maine-eDNA EPSCoR program, one of the main focuses is to understand and characterize community assemblages in the Gulf of Maine (GoM) using eDNA to further inform conservation, monitoring, and sustainability. In this study, I selected a subset of the best performing vertebrate and invertebrate metabarcoding assys to test against GoM species present in the …

Evaluation Of The Effectiveness Of Ventless Trap Survey In Capturing Sublegal American Lobster Abundance In The Inshore Gulf Of Maine, Shiyue Zhao

Electronic Theses and Dissertations

The stock assessment of American lobster (Homarus americanus) plays an important role in managing the fishery in the Gulf of Maine (GOM). Various fishery-dependent and fishery-independent data are required in the stock assessment to estimate key fisheries parameters that define the population dynamics of American lobster. In the 2015 benchmark stock assessment, ventless trap survey (VTS) data were included for the first time to provide information about the sublegal lobster (carapace length < 83 mm) dynamics. However, the effectiveness of VTS data in monitoring sublegal lobsters has not been evaluated and we have little information on whether the VTS sampling design can capture sublegal lobster dynamics. The primary goal of this thesis research was to evaluate and determine whether the data collected from the Maine VTS provide robust estimation of design-based sublegal lobsters abundance index in the inshore GOM. To achieve this goal, I (1) estimated and evaluated variations in catch rates derived, respectively, from the first, second, and third ventless trap per site; 2) predicted sublegal lobster population at a high spatial resolution using generalized additive models (GAMs); (3) sampled the simulated sublegal lobster population following the sampling protocol used in the VTS program to derive a simulated VTS abundance index; and 4) compared the simulated VTS abundance index with the

predicted population abundance index in the simulated sublegal lobster population. The spatial scale of the study was defined by the National Marine Fisheries Service (NMFS) statistical areas in …

Evaluating The Foraging Ecology And Energetics Of Atlantic Bluefin Tuna (Thunnus Thynnus) In The Gulf Of Maine, Samantha Nadeau

Electronic Theses and Dissertations

Atlantic bluefin tuna (Thunnus thynnus, ABFT) have been a commercially and recreationally valuable species in the Gulf of Maine (GOM) since the early 1950s. Over the past few decades, abundance, spatial distribution, and physical condition of ABFT have shifted, possibly as a result of trophic changes including the composition, distribution, and/or condition of available prey. Historically, ABFT forage has most commonly consisted of Atlantic herring (Clupea harengus), Atlantic mackerel (Scomber scombrus), squids (Cephalopoda), bluefish (Pomatomus saltatrix), and sand lance (Ammodytes spp.). The current stock assessment for Atlantic herring, the dominant prey item for ABFT, suggests a reduction in spawning stock …

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 …

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. …

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 …

Examining Scale-Dependent, Nonstationary Environmental Effects On American Lobster (Homarus Americanus) Spatial Distribution And Habitat Suitability In A Changing Gulf Of Maine, Jamie Behan

Electronic Theses and Dissertations

The Gulf of Maine (GOM) is a highly complex environment and previous studies have suggested needs to account for spatial nonstationarity in species distribution models for the American lobster (Homarus americanus). Spatial nonstationarity can be defined as the presence of variation in relationships between independent and dependent variables across space (Windle et al., 2012). To explore impacts of spatial nonstationarity on species distribution, models with the following three assumptions were compared: (1) stationary relationships between species distributions and environmental variables; (2) nonstationary density-environment relationships between eastern and western GOM, and (3) nonstationary density-environment relationships across eastern, central, and western GOM. …

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 …

Integrating Local Ecology And Human Dimensions To Understand A Tidally Dynamic Ecosystem In Downeast Maine, Gabriella Marafino

Electronic Theses and Dissertations

Coastal community resilience requires connecting people with useful information that reflects their needs and interests and empowers them to make informed marine resource decisions. In this thesis, I explore how to effectively integrate disparate data from different disciplines and sources to make information more useful and usable at federal, state, tribal, and local levels in order to support more holistic and integrated management. To accomplish this, I draw on different types of knowledge and approaches, including Western science, local ecological knowledge, traditional ecological knowledge, and citizen science, to incorporate the social perspective and community values for holistic marine resource management. …

Assessing Predator Risk To Diadromous Fish Conservation In The Penobscot River Estuary, Lauri Leach

Electronic Theses and Dissertations

Successful conservation of pinnipeds in the northwest Atlantic has led to increasing populations of harbor (Phoca vitulina) and gray seals (Halichoerus grypus) in the Gulf of Maine. Seals are often perceived as predators and competitors for fish, and as a result, come into conflict with fisheries and fish conservation. Increasing numbers of seals have become a recent concern in the Penobscot River Estuary in Maine, as habitat restoration and diadromous fish conservation have been top priorities in this region for the past decade.

To understand how pinnipeds are responding to these efforts, as well as the risks they pose to …

Senders, Receivers, And Spillover Dynamics: Understanding Transformative Forces Of Aquaculture In The Marine Aquarium Trade, Bryce Risley

Electronic Theses and Dissertations

Industry and academic conversations on aquaculture’s role in the marine aquarium trade are often centered on production advancements, biological and reproductive constraints of concerned species, and conservation deliverables and often overlook the possible socioeconomic consequences of aquaculture production. Due attention is yet to be spent on understanding broader stakeholder sentiment on aquaculture production and the toll it may have on specialized suppliers such as those in the Sri Lankan marine ornamental fishery. Utilizing a framework derived from Coupled Human and Natural Systems, research found suppling stakeholders predominantly unable to participate in aquaculture production due to various access limitations. When viewed …

How Students Communicate Knowledge: Written Versus Drawn Responses To Formative Assessment Questions In An Introductory Undergraduate Marine Science Course, Christina Siddons

Electronic Theses and Dissertations

Undergraduate science education suffers from a lack of concrete instructional strategies that address real-world postgraduate skills such as visual literacy and science communication. Research within marine science education especially lags behind other, more well-researched fields such as physics or mathematics education, both of which have extensive literature addressing specific instructional strategies that instructors can implement in the classroom. Undergraduate marine science programs overlap with content areas from chemistry, physics, and biology, and provide a rich opportunity for examining how to include more authentic educational experiences in an undergraduate classroom. However, the types of assessments that are typically employed tend to …

From Phocine Distemper To Avian Influenza: A Study Of Immunogenetic Diversity In Two Sympatric Pinniped Species, Alayna K. Gigliotti

Electronic Theses and Dissertations

Gray (Halichoerus grypus) and harbor (Phoca vitulina) seals are sympatric species that inhabit the North Atlantic and have been subject to mortality events from disease outbreaks, particularly phocine distemper and avian influenza virus. Across mortality events, gray seals tend to exhibit a higher survival rate, which could be explained by various ecological factors impacting rates or direction of selection in parts of the genome related to the immune system. These factors could include haul-out site density, habitat, and degree of inter/intraspecies interaction. This research aims to compare genetic diversity within the Major Histocompatibility Complex (MHC) class …

Distributions And Abundances Of The Red Tide Dinoflagellate Alexandrium Catenella In The Eastern Gulf Of Maine And Bay Of Fundy In Relation To Diatoms In June, July And August Of 2019, Kimberly Lina D'Adamo

Electronic Theses and Dissertations

A series of three oceanographic survey cruises were conducted in June, July, and August of 2019 in the northeastern Gulf of Maine and Bay of Fundy. Surface water samples were collected and analyzed for enumerations of cell densities of the dinoflagellate Alexandrium catenella in relation to cell densities of diatoms. Hydrographic profiles of temperature, salinity, and nutrients (silicate and nitrate) were also made at each station. Data were analyzed to determine if there was any statistically significant evidence of allelopathic interference imparted by diatoms that impede A. catenella. A. catenella cells were most abundant in June, reaching 6,195 cells per …

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 …

Sourcing And Evaluating The Use Of Detritus As A Supplementary Diet For Bivalve Aquaculture Using Stable Isotopes And Fatty Acid Biomarkers, Adrianus C. Both

Electronic Theses and Dissertations

Detritus is a ubiquitous component of ecosystems and an important fuel for secondary production. Due to the extractive nature of bivalve aquaculture, detritus is often incorporated into carrying capacity and growth models for cultured bivalves. However, despite the complexity and difficulty in obtaining direct measurements, detritus is often treated as a homogeneous food source in models. Further understanding the role detritus plays in the diet of cultured bivalves could lead to more comprehensive and accurate models as well as more informed site selection for growers. The purpose of this study was to assess the abundance, bioavailability, and contribution of detritus …

Evaluating Seafood Distribution Channels In The Atlantic Sea Scallop And Northeast Multispecies Groundfish Fisheries, Amanda Fall

Electronic Theses and Dissertations

Federal fisheries policy in the United States aims to balance resource conservation with maximum sustainable use. Catch shares are a quota-based management tool that are being increasingly deployed to achieve this ambitious goal. One perceived benefit of catch shares is that they give fishermen control of their catch so they will have the latitude to pursue the most profitable marketing arrangements. Using a mixed-methods approach, this research seeks to (1) describe and document the different marketing strategies that commercial fishermen in the Northeast Multispecies Groundfish and Atlantic Sea Scallop fisheries are using to sell their catch; and (2) estimate the …