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Collaborative And Engaged Research To Strengthen Equity And Adaptive Governance In Co-Managed Fisheries, Gabrielle V. Hillyer Aug 2023

Collaborative And Engaged Research To Strengthen Equity And Adaptive Governance In Co-Managed Fisheries, Gabrielle V. Hillyer

Electronic Theses and Dissertations

Small-scale, co-managed fisheries are found throughout the world and often represent intertwining cultures, societies, communities, economies, institutions, and governments. They face complex issues, derived from ecological and social sources. Solving these issues requires diverse expertise, often developed through engaged methodologies which can facilitate collaborative solution creation between researchers, community members, and others. In this dissertation, I demonstrate the benefits of these engaged methodologies and review how they, when coupled with anticolonial approaches to research, can create more equitable solutions to complex issues. This dissertation focuses on multiple projects within the wild clam fishery in Maine including: (1) the creation of …


Biophysical Factors Impacting Sea Lice Settlement And Survival, Eleanor R. Glahn May 2023

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 May 2023

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 …


Post-Harvest Treatment Effects On Physicochemical Quality Attributes Of North Atlantic Squid Doryteuthis Pealeii And Illex Illecebrosus, Caitlin M. Hillery May 2023

Post-Harvest Treatment Effects On Physicochemical Quality Attributes Of North Atlantic Squid Doryteuthis Pealeii And Illex Illecebrosus, Caitlin M. Hillery

Electronic Theses and Dissertations

Doryteuthis pealeii (longfin inshore squid) and Illex illecebrosus (Northern shortfin squid) are the two most commercially important species of squid harvested in the United States. They are also the only two species of squid in the world certified sustainable by the Marine Stewardship Council. Despite their pivotal role in the U.S. seafood industry, very little research has been performed on their quality in decades. Two common methods of freezing and secondary processing applied to squid in the U.S. industry are blast-freezing either at sea or on land; and leaving the squid whole, or fully cleaning and then brining them. To …


Barriers To And Opportunities For Adoption In Maine’S Aquaculture Industry, Caitlin Cleaver Dec 2022

Barriers To And Opportunities For Adoption In Maine’S Aquaculture Industry, Caitlin Cleaver

Electronic Theses and Dissertations

Aquaculture, or the farming of marine species, can diversify coastal economies, but development of this industry is hindered by negative perceptions or regulatory constraints. Commercial fishers are logical adopters of aquaculture, but can also mount opposition to its growth. This dissertation utilized innovation theory to understand fishers’ perceptions of and willingness to adopt aquaculture and drivers of and barriers to scallop aquaculture development in Maine (USA). Through a mail survey, lobster fishers’ perceptions of Maine’s aquaculture industry and their willingness to adopt aquaculture were assessed (Chapter 2). Individuals who were more satisfied with government management of aquaculture held more positive …


Using Reflex Actions To Predict Delayed Post-Harvest Mortality Of American Lobster (Homarus Americanus) In Maine’S Lobster Supply Chain, Cassandra Leeman Dec 2022

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 …


Developing And Characterizing A Novel Tempo Cnf Hydrogel Adjuvant And Delivery System For Aquatic Vaccines, Kora Kukk Aug 2022

Developing And Characterizing A Novel Tempo Cnf Hydrogel Adjuvant And Delivery System For Aquatic Vaccines, Kora Kukk

Electronic Theses and Dissertations

Aquaculture is a large part of the food production sector which is greatly expanding. One of the largest losses in aquaculture is due to pathogens. Current solutions for protecting farmed finfish from pathogens can be very expensive with variable efficiency. Current disease prevention strategies include vaccination. Types of vaccines include immersion vaccines, feed vaccines, and injectable vaccines. The most popular solution is oil-based injectable vaccines due to its protection. However, the oil-based adjuvant used in most of these formulations causes adverse reactions in the fish including reduced growth. These vaccines require multiple administrations throughout the fish’s lifetime causing unwanted handling …


Weaving An Interdisciplinary Microbiome Career Using Threads From Different Ecosystems, Sarah Hosler Aug 2022

Weaving An Interdisciplinary Microbiome Career Using Threads From Different Ecosystems, Sarah Hosler

Electronic Theses and Dissertations

Animals have trillions of microorganisms living in or on many body sites, these communities of microorganisms are called microbiomes. Microbiomes are typically host-specific, and a lot of information about the host can be determined from investigating them. Microbiome research has many real-world applications, and this thesis utilizes the One Health perspective, which acknowledges the connection of humans, animals, and environments, and emphasizes the need for collaborative, interdisciplinary research. The first interdisciplinary project is an investigation into the bacteria in wild and cultured Atlantic deep-sea scallop, Placopecten magellanicus larvae. Adults in hatcheries can be induced to spawn, but the last two …


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 …


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 …


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 …


Sustainable Production Of Feed For Recirculating Aquaculture Using Black Solider Flies And Microalgae, Patrick Erbland Dec 2020

Sustainable Production Of Feed For Recirculating Aquaculture Using Black Solider Flies And Microalgae, Patrick Erbland

Electronic Theses and Dissertations

The demand for high-quality, nutritious food continues to increase as human populations grow. As wild fisheries are depleted, aquaculture production is growing to meet the demand for seafood. Sustainable alternatives to wild caught fish meal are increasingly valued for aquaculture feed production. Microalgae and insect larvae are both valuable sources of fatty acids in aquaculture feed. Black soldier fly larvae, Hermetia illucens (L.) are used to convert organic waste streams into insect-based animal feeds. We tested their ability to retain alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) from feeding substrates, which has important implications for their use …


Holistic Monitoring Of Maine Sea Lice (Lepeoptheirus Salmonis, Kroyer, 1837) Sensitivities To Therapies: Developing A Novel Assay To Examine Lice Behavior, Kathryn Liberman Dec 2020

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 …


Uncertainties And Robustness In Fisheries Stock Assessment And Management: Data Processing, Modeling And Socioeconomic Aspects, Luoliang Xu Nov 2020

Uncertainties And Robustness In Fisheries Stock Assessment And Management: Data Processing, Modeling And Socioeconomic Aspects, Luoliang Xu

Electronic Theses and Dissertations

The main uncertainties that affect the quality of fisheries stock assessment and pose great challenges to fisheries management can stem from a wide range of sources including observation errors associated with model input data, dynamic model process errors, model structure misspecifications, and/or volatile fishery-related socioeconomic environment. Many assessment and management failures are in part attributed to inappropriate consideration of different uncertainties. For many traditional stock assessment models, the observation error is the only source of uncertainty that modelers explicitly deal with. The observation error is usually assumed to be random. The objective functions are formulated by the corresponding distributions (e.g., …


Movement And Survival Of Atlantic Salmon Smolts In The Penobscot River, Maine, Alejandro Molina Moctezuma Aug 2020

Movement And Survival Of Atlantic Salmon Smolts In The Penobscot River, Maine, Alejandro Molina Moctezuma

Electronic Theses and Dissertations

The Penobscot River system hosts the largest population of endangered Atlantic salmon Salmo salar in the United States. However, total adult returns in this river remain low. Historically low numbers led to listing of the distinct population segment (DPS) in 2000, and the Penobscot River population was included in the DPS in 2009. Reducing mortality in all life stages is crucial for the recovery of Atlantic salmon populations. One of the life stages associated to high mortality is the juvenile stage (smolts), in which individuals migrate downstream towards the estuary. During this migration smolts face a series of new conditions …


The Effects Of Sediment Acidification And Temperature On The Immune Capacity Of The Atlantic Jackknife (Razor) Clam (Ensis Leei M. Huber, 2015), Brian Preziosi Dec 2019

The Effects Of Sediment Acidification And Temperature On The Immune Capacity Of The Atlantic Jackknife (Razor) Clam (Ensis Leei M. Huber, 2015), Brian Preziosi

Electronic Theses and Dissertations

Sediment acidification has been shown to negatively impact clams of economic importance such as the soft-shell clam, Mya arenaria Linnaeus, 1758, and hard clam, Mercenaria mercenaria (Linnaeus, 1758). Effects of sediment acidification on razor clams, including the Atlantic jackknife clam Ensis leei M. Huber, 2015, are unknown. E. leei has been identified as a species with potential for aquaculture operations on the New England coast. E. leei may be resilient to acidification and thus persist in acidified sediments where other clams cannot. To this end, the impact of acidified surface sediment on the internal immune capacity of adult (mean shell …


Fish Passage And Hydropower: Investigating Resource Agency Decision-Making During The Ferc Hydropower Relicensing Process, Sarah Vogel Dec 2019

Fish Passage And Hydropower: Investigating Resource Agency Decision-Making During The Ferc Hydropower Relicensing Process, Sarah Vogel

Electronic Theses and Dissertations

Hydropower dams represent a significant challenge for the successful migration of sea-run fish, many species of which are in decline. Most hydropower dams in the United States are regulated by the Federal Energy Regulatory Commission (FERC), an independent federal agency responsible for granting 30 to 50-year licenses to projects for their continued operation. Licenses typically include conditions for the conservation of sea-run fish such as fish passage construction, operational changes, monitoring of effectiveness, and other mitigative conditions. While FERC remains the primary authority in licensing, the current regulatory framework stipulates input from other federal and state resource and regulatory agencies, …


Getting Over The Dam: Overcoming Institutional Barriers To The Recovery Of Atlantic Salmon By Navigating The Social-Science/Policy Interface, Melissa E. Flye Dec 2019

Getting Over The Dam: Overcoming Institutional Barriers To The Recovery Of Atlantic Salmon By Navigating The Social-Science/Policy Interface, Melissa E. Flye

Electronic Theses and Dissertations

The term governance has undergone somewhat of an evolution since its inception, originally describing the act of governing, it has come to represent a more collaborative form of governing which is distinct from hierarchical control models (Marin and Mayntz, 1991). Collaborative governance refers to the systems associated with public policy decision making and resource management which span the jurisdictional boundaries of public agencies, levels of government, and/or public and private spheres in order to pursue a public policy goal or outcome (Emerson et al., 2012). Environmental management is often considered an inherently collaborative effort, as ecological systems and species rarely …


Examining Citizens' Preferences For Aquaculture Using Discrete Choice Experiments, Olga Bredikhina May 2019

Examining Citizens' Preferences For Aquaculture Using Discrete Choice Experiments, Olga Bredikhina

Electronic Theses and Dissertations

Over the last few decades, discrete choice experiments (DCEs) have become increasingly popular across different subfields of economics as a way to elicit citizens‟ stated preferences for product and service attributes as well as various environmental and infrastructure features. The DCE framework could be seen as a time- and cost-effective alternative to the revealed preferences framework that is based on data obtained using transactions observed in real-world markets. DCEs offer the advantage over revealed preferences data because they allow learning about consumer preferences for hypothetical products or product attributes without bearing the costs of introducing new products to the market. …


Assessing Migrations And Habitat Connectivity For Two Anadromous Species Following A Major Restoration Effort In The Penobscot River, Maine, George A. Maynard May 2019

Assessing Migrations And Habitat Connectivity For Two Anadromous Species Following A Major Restoration Effort In The Penobscot River, Maine, George A. Maynard

Electronic Theses and Dissertations

The construction of industrial dams across major rivers in New England began in the early 1800s with textile mills in Massachusetts. Because of its legacy of mill dams and log driving dams, New England has the highest density of dams anywhere in North America, averaging one dam for every 44 km2 of drainage area. By the early 1900s, these dams drastically limited migrations by diadromous fishes, resulting in declines in populations of migratory fishes, including Atlantic salmon Salmo salar and American shad Alosa sapidissima. Since that time, different fishway designs and river management plans have been tried around …


The Infection Dynamics Of Sea Lice On Atlantic Salmon (Salmo Salar) In Cobscook Bay, Maine, Usa, Catherine Anne Frederick Dec 2018

The Infection Dynamics Of Sea Lice On Atlantic Salmon (Salmo Salar) In Cobscook Bay, Maine, Usa, Catherine Anne Frederick

Electronic Theses and Dissertations

Sea lice (Lepeophtheirus and Caligus spp) are parasitic copepods that infect the external surfaces of fish hosts. Salmon lice (L. salmonis) outbreaks are commonly reported by operations in Canada, Norway, Scotland, Ireland, and the United States and are a primary concern in aquaculture because of their fish health and economic impacts. When farmed fish mortalities and treatments are accounted for, annual losses from sea louse infestations exceed $300,000,000 (Costello 2009). Farms experiencing sea lice infections risk on-site re-infection and transmission to wild populations and other farms that are hydrographically connected. In Maine, Atlantic salmon farms are located in the northeast, …


Black Soldier Fly Larvae As Value-Added Feed For Aquaculture In Maine, Joshua Villazana Dec 2018

Black Soldier Fly Larvae As Value-Added Feed For Aquaculture In Maine, Joshua Villazana

Electronic Theses and Dissertations

Black soldier flies (BSF), Hermetia illucens (Linnaeus) (Diptera: Stratiomyidae) consume decaying organic waste as larvae (BSFL) and can be used for recycling a variety of biogenic wastes. BSFL can also be processed into value-added animal feeds, including those used in aquaculture. An overarching goal of this project was to obtain additional insights into BSF biology to improve their rearing and handling in future mass-production facilities serving Maine aquaculture.

We tested BSFL growth in the laboratory on seven seafood wastes from Maine fish processing facilities. Substrates potentially suitable for BSFL rearing included finfish trimmings, wet sea cucumber, dry quahog, and sea …


Investigating Present-Day Health Issues Of The American Lobster (Homarus Americanus), Deborah A. Bouchard May 2018

Investigating Present-Day Health Issues Of The American Lobster (Homarus Americanus), Deborah A. Bouchard

Electronic Theses and Dissertations

The American lobster, Homarus americanus, H. Milne Edwards, 1837, supports the most economically valuable fishery along the North Atlantic coast of North America. A collapse in lobster populations in Southern New England (SNE) has coincided with increasing ocean temperatures and emerging diseases. This research investigated the etiologies of limp lobster disease (LLD) and epizootic shell disease (ESD), two diseases that continue to cause significant mortality in natural lobster populations. Mortality from LLD is associated with the bacteria Photobacterium indicum and is more intense in impounded lobsters. To more clearly define the community ecology of this suspected opportunistic pathogen, the microbial …


Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish May 2018

Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish

Electronic Theses and Dissertations

Of the most iconic fish species in the world, the Atlantic cod (Gadus morhua, hereafter, cod) has been a mainstay in the North Atlantic for centuries. While many global fish stocks have received increased pressure with the advent of new, more efficient fishing technology in the mid-20th century, exceptional pressure has been placed on this prized gadoid. Bycatch, or the unintended catch of organisms, is one of the biggest global fisheries issues. Directly resulting from the failed recovery of cod in the GoM, attention has been placed as to possible sources of unaccounted catch. Among the most …


Incorporating Environmental Variability Into Assessment And Management Of American Lobster (Homarus Americanus), Kisei Tanaka May 2018

Incorporating Environmental Variability Into Assessment And Management Of American Lobster (Homarus Americanus), Kisei Tanaka

Electronic Theses and Dissertations

The American lobster (Homarus americanus) support one of the most valuable fisheries in the United States. A growing body of literature recognizes the importance of environmental variables in regulating this species’ biogeography and population dynamics. However, the current lobster stock assessment and management do not explicitly consider the impact of environmental variables such as water temperature and assumes spatiotemporal variabilities in the lobster environment as random background noises. Furthermore, while climate-induced changes in marine ecosystems continue to impact the productivity of lobster fisheries, studies that model lobster response to altered environmental conditions associated with climate change are lacking. …


Assessing Economic Performance Of Maine's Lobster Fleet Under Changing Ecosystem Conditions In The Gulf Of Maine, Alexa M. Dayton May 2018

Assessing Economic Performance Of Maine's Lobster Fleet Under Changing Ecosystem Conditions In The Gulf Of Maine, Alexa M. Dayton

Electronic Theses and Dissertations

This research evaluates lobster producer efficiency and considers fleet wide economics and policy implications in support of changing marine ecosystems in the Gulf of Maine. We conducted a comprehensive lobster industry survey to assess costs and effort expended at the producer level for a representative fishing year, and establish a series of production function performance baselines for future comparison. The demographic data, attitudes and valuations collected allow us to characterize the fishing effort and regional dependency on the resource. We look at the Maine Lobster limited entry licensing system, to understand how the future participation in the fishery might change, …


Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver Aug 2017

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver

Electronic Theses and Dissertations

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase.

Historically, …


Investigating Factors Contributing To Reduced Embryo Survival In Farm Raised Atlantic Salmon, Salmo Salar L., Leeanne Thayer Aug 2017

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 …