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Full-Text Articles in Life Sciences

Two Bioeconomic Studies On Haddock Culture: Live Feed And Juvenile Production, Kate M. Waning Dec 2002

Two Bioeconomic Studies On Haddock Culture: Live Feed And Juvenile Production, Kate M. Waning

Electronic Theses and Dissertations

The State of Maine is reliant upon its natural resources. Wild catches of marine finfish, especially ground fish such as cod and haddock, are declining. In addition, several new restrictions have been placed on the culture of Atlantic salmon due to its listing under the Endangered Species Act. These issues serve as an impetus to explore the development of alternative species for cold-water marine aquaculture. This research focuses on early haddock culture. The two areas where haddock culture varies from production of other species are the need for live feeds and proximity to seawater. Unlike salmon, haddock spend their entire …


The Effect Of Temperature On The Development, Growth And Survival Of Atlantic Cod (Gadus Morhua) During Early Life-Histories, Adrian Jordaan Dec 2002

The Effect Of Temperature On The Development, Growth And Survival Of Atlantic Cod (Gadus Morhua) During Early Life-Histories, Adrian Jordaan

Electronic Theses and Dissertations

For poikilothennic animals, and in particular those that inhabit aquatic habitats, temperature has a significant effect on all life processes. The purpose of this research was to investigate the contribution of temperature on embryonic development and survival and its effect on vital rates. Of particular interest was what aspect(s) of egg and larval life-histories are most affected by temperature and what consequence temperature effects may have on cumulative mortality. Three batches of Atlantic cod (Gadus morhua) eggs were acquired from a Newfoundland source of adult broodstock held at 4555°C. The eggs were divided andacclimated to four constant temperature regimes at …


Evaluation Of Three Potential Methods For Preventing The Spread Of The Salmon Louse, Lepeophtheirus Salmonis (Kreyer, 1837), Micheal Pietrak Dec 2002

Evaluation Of Three Potential Methods For Preventing The Spread Of The Salmon Louse, Lepeophtheirus Salmonis (Kreyer, 1837), Micheal Pietrak

Electronic Theses and Dissertations

Lepeophtheirus salmonis or salmon lice infections are one of the most prevalent parasitic infections in the salmon aquaculture industry. Salmon lice cause an estimated loss of 3% of the production of Maine's salmon industry annually. Within the State of Maine only a portion of the farm sites experience salmon lice infections on an annual basis, while some sites have never had infections of Lepeophtheirus salmonis. Because of the potential impact that salmon lice infections could mean to those areas that to date have been fiee of L. salmonis infections, there has been concern both on the part of the State …


A New Apex Predator In The Gulf Of Maine? Large, Mobile Crabs (Cancer Borealis) Control Benthic Community Structure, Amanda V. Leland Dec 2002

A New Apex Predator In The Gulf Of Maine? Large, Mobile Crabs (Cancer Borealis) Control Benthic Community Structure, Amanda V. Leland

Electronic Theses and Dissertations

Apex predators can control community structure by preying on strongly interacting species at lower trophic levels. Fishing of apex predators in the marine realm often results in herbivore dominated systems. In the Gulf of Maine, coastal subtidal communities became dominated by grazing green sea urchins (Strongylocentrotus droehachiensis) following the extirpation of large, predatory groundfish from coastal zones. Subsequent depletion of sea urchins since the late 1980s functionally eliminated this dominant herbivore from vast regions. Sea urchin recruitment is low or nonexistent in communities dominated by fleshy algae that have developed since the decline of sea urchin populations. We hypothesized that …


Modeling The Role Of No-Take Marine Reserves In Fisheries Management, Deidre F. Gilbert Dec 2002

Modeling The Role Of No-Take Marine Reserves In Fisheries Management, Deidre F. Gilbert

Electronic Theses and Dissertations

In recent years there has been increasing interest in the potential of no-take marine reserves to benefit fisheries management. Scientific reviews have shown that reserves often lead to substantial increases in the density, biomass, size and diversity of marine fishes inside their boundaries. However, little empirical work has been done to determine the effect of reserves on the fisheries outside their boundaries, such as potential changes in yield, size of fleet, or variability in catch. In order to explore the interaction between the biological growth and dispersion processes of the harvested stock and the changing economic incentives of harvesters created …


Evolution Of Lake Malawi Cichlid Fishes (Perciformes: Teleostei), Peter F. Smith Dec 2002

Evolution Of Lake Malawi Cichlid Fishes (Perciformes: Teleostei), Peter F. Smith

Electronic Theses and Dissertations

The cichlid fish species flocks of East Africa provide a compelling model system in which to study the process of speciation. In Lake Malawi, greater than 1000 species of cichlids have emerged since the filling of the lake basin about 1 million years ago. Over 99% of the Lake Malawi haplochromine cichlids are endemic, suggesting that most of this diversification has taken place within the temporal and spatial boundaries set by the Lake's shores. Moreover, many of these species are endemic to small areas within the lake, indicating that speciation has occurred very recently or perhaps is in progress in …


Systematics Of The Cumacea (Crustacea), Pilar A. Haye Dec 2002

Systematics Of The Cumacea (Crustacea), Pilar A. Haye

Electronic Theses and Dissertations

Cumaceans are small benthic crustaceans. They have a marine cosmopolitan distribution with diversity increasing with depth. There are approximately 1,400 described species of cumaceans. Despite the fact that they offer a good model for the study of morphological evolution and biogeography, the studies on the Order Cumacea are almost restricted to work at the alpha taxonomy level. This thesis contributes to the systematics of Cumacea. The phylogenetic relationships within the Cumacea were studied using newly obtained partial amino acid sequences from the mitochondria1 gene Cytochrome Oxidase I. Among other findings, phylogenetic analyses revealed that the families Bodotriidae, Leuconidae, and Nannastacidae, …


Jock Darling: The Notorious “Outlaw” Of The Maine Woods, James B. Vickery Iii Oct 2002

Jock Darling: The Notorious “Outlaw” Of The Maine Woods, James B. Vickery Iii

Maine History

Jim Vickery began work on this article shortly before he died in 1997. He had been researching Jock Darling for several years, and at my urging he set down his thoughts on the “old outlaw” under an arrangement by which he would compose the article on one of his infamous "yellow pads,” and I would transcribe the results on my computer and return a clean copy to him for editing and proofreading. He would also fill in the blanks where I could not decipher his handwriting. Before we could complete this project, Jim was hospitalized with the condition that finally …


An Examination Of The Georges River Clam Management Program, Kristin E. Togue Brawn Aug 2002

An Examination Of The Georges River Clam Management Program, Kristin E. Togue Brawn

Electronic Theses and Dissertations

This thesis examines the Georges River Clam Management Program, a multi-town interlocal harvesting and management plan in mid-coast Maine. It discusses relevant economic and communal action theory, and examines their application to the development of the program. Chapter 1 reviews the purposes and methods of the study. Chapter 2 reviews the relevant clam biology necessary to understand the principles of soft-shell clam management. Chapters 3 and 4 provide the history and background of clam harvesting and management in Maine. Chapter 5 discusses the Georges River Program, including the factors that led to its development and the details of its organization …


A Pilot Study To Test Ventless Traps As A Means To Quantify Populations Of The American Lobster (Homarus Americanus), Carin Louise Poeschel Aug 2002

A Pilot Study To Test Ventless Traps As A Means To Quantify Populations Of The American Lobster (Homarus Americanus), Carin Louise Poeschel

Electronic Theses and Dissertations

The American lobster, Homarus americanus, is Maine's most valuable marine fishery. The state of Maine has an economic interest in the protection of this resource. The health of this industry depends on effective management for sustainability. However, there is little quantitative information on American lobsters less than harvestable size. A study was conducted to evaluate the utility of traps modified to catch sublegal lobsters. With the aid of fishernlen fiom six of the eight Maine coastal counties over a four-month time period (July through October, 2000), data were recorded to compare catch rates in experimental traps with no escape vents …


Relationships Between Stream Geomorphology And Fish Community Structure And Diversity In Maine, Emily Gaenzle Aug 2002

Relationships Between Stream Geomorphology And Fish Community Structure And Diversity In Maine, Emily Gaenzle

Electronic Theses and Dissertations

Predicting patterns in species distribution and abundance for resource management and conservation is a major focus of applied ecology. The primary objective of this study was to determine if there is a predictable relationship between stream geomorphology and fish community structure, native species richness, and native salmonid abundance in Maine. Specifically, I examined relationships between fish assemblages and geomorphic stream types, as delineated by the Rosgen classification system (Rosgen 1996). Fifty-three stream reaches in Maine were classified, and fish communities within the reaches were characterized using backpack electrofishing. Species richness was lowest in A-type streams (i.e., steep, entrenched, confined), which …


An Assessment Of Methods For Testing The Reliability Of Wildlife Occurrence Models Used In Gap Analysis, Sandra M. Schaefer Aug 2002

An Assessment Of Methods For Testing The Reliability Of Wildlife Occurrence Models Used In Gap Analysis, Sandra M. Schaefer

Electronic Theses and Dissertations

Habitat association models designed to predict species occurrence are often tested by comparing predictions to field observations. Two types of error are then reported, omission (Yo of species not predicted but present on a site) and commission (% of species predicted but not present on a site). The purpose of this research was to assess the Maine Gap Analysis vertebrate predictions using the traditional site-specific approach and to determine what factors influence the amounts of error reported. I also developed a species-specific approach for testing the accuracy of the vertebrate predictions and compared these results to the site-specific method. When …


Systematics Of Northeastern Meadow Vole (Microtus Pennsylvanicus) Subspecies, With Empasis On The Island Endemic (M. P. Shattucki, Howe 1901) In Penobscot Bay, Maine, Jennifer Marie Lowry Aug 2002

Systematics Of Northeastern Meadow Vole (Microtus Pennsylvanicus) Subspecies, With Empasis On The Island Endemic (M. P. Shattucki, Howe 1901) In Penobscot Bay, Maine, Jennifer Marie Lowry

Electronic Theses and Dissertations

The Penobscot meadow vole (Microtus pennsylvanicus shattucki) (PMV) is an insular subspecies of meadow vole (M. pennsylvanicus) inhabiting the islands of North Haven, Islesboro, and Tumbledown Dick in Penobscot Bay, Maine. It is one in a suite of island meadow vole subspecies which has been described from southern New England through eastern Canada. The subspecific recognition of M. p. shattucki, along with the others in this group, was solely based on a univariate analysis of a few morphological characters, which has fostered debate about the validity of the subspecies. Despite this uncertainty, the taxonomy is …


Overcoming Transaction Cost Impediments To Resolving The Dilemma Of Collective Action In The New England Fisheries, William J. Brennan May 2002

Overcoming Transaction Cost Impediments To Resolving The Dilemma Of Collective Action In The New England Fisheries, William J. Brennan

Electronic Theses and Dissertations

Management of many global marine fisheries have faltered under science-based government-sponsored management regimes. While the result has often been biological stock failures and consequent socio-economic problems, there are instances where enhanced conservation efforts have led to fishery management success. Studies of New England fisheries reveal that the relative success of fishery management can be explained in terms of the interaction between the fishing industry and the government, the relative power of each in the fishery management exchange, the degree to which information and perceptions about the fishery are comparable, the scale and complexity of the fishery to be managed, and …


Marine Protected Areas In The Gulf Of Maine: Policy For A Common Resource, Carolyn F. Skinder May 2002

Marine Protected Areas In The Gulf Of Maine: Policy For A Common Resource, Carolyn F. Skinder

Electronic Theses and Dissertations

In the wake of 25 years of unsuccessful single-fisheries management in the Gulf of Maine, there has been growing support for reform. Ecosystem management has been proposed as one alternative, but the information needed to manage whole ecosystems is greatly lacking. Implementing fully-protected marine protected areas (MPAs) is one way to preserve habitat while at the same time acquiring data for future ecosystem management. Under the current institutional arrangement in the Gulf, engineering agreement for MPAs is difficult due to the differing goals of varied user groups. The situation is reflective of a common property resource problem in that there …


The Value Of Rockweed (Ascophylum Nodosum) As Habitat For Tidepool Fishes, Amy Marie Gullo Jan 2002

The Value Of Rockweed (Ascophylum Nodosum) As Habitat For Tidepool Fishes, Amy Marie Gullo

Electronic Theses and Dissertations

Tidepool fishes are an interesting and commercially valuable guild of fishes that reside in tidepools at low tide. Tidepool fishes of the North Atlantic Coast reside in tidepools only during the late spring to Ml months, and are typically juveniles of subtidal adult species. Tidepool fishes on the Pacific Coast of North America have been studied extensively, but species of the North Atlantic Coast have rarely been studied. An important area of study is the use of different tidepool microhabitats by fishes, specifically the use of rockweed (AscophyZZum nodosum) fringe, which is present in many tidepools. Rockweed is an algal …


Picturing Nature: Education, Ornithology And Photography In The Life Of Cordelia Stanwood: 1865-1958, Cynthia Watkins Richardson Jan 2002

Picturing Nature: Education, Ornithology And Photography In The Life Of Cordelia Stanwood: 1865-1958, Cynthia Watkins Richardson

Electronic Theses and Dissertations

The field of environmental history, with a few exceptions, has neglected gendered analysis; in addition, several women's histories have analyzed a few environmental issues, but disregard environmental scholarship. In the joining of women's and environmental history, this dissertation examines the life of one woman, Cordelia J. Stanwood of Ellsworth, Maine (1865-1958), to determine how a woman could use nature to transcend the social limits of domesticity in the early twentieth century. Research of her correspondence, published writing, photography and forty years of field notes reveals that like many other women, she took advantage of technology and evolving ideas about womanhood …


The Relationship Between Green Sea Urchin Spawning, Spring Phytoplankton Blooms, And The Winter-Spring Hydrography At Selected Sites In Maine, Lindsay C. N. Seward Jan 2002

The Relationship Between Green Sea Urchin Spawning, Spring Phytoplankton Blooms, And The Winter-Spring Hydrography At Selected Sites In Maine, Lindsay C. N. Seward

Electronic Theses and Dissertations

The relationship between green sea urchin spawning, spring phytoplankton blooms, and hydrography were examined at multiple spatial scales during the winter-spring of 2000 at selected sites along the coast of Maine. To determine factors contributing to the variation observed in the timing of green sea urchin spawning, sea urchins, phytoplankton, and oceanographic variables were sampled biweekly at four sites in central Maine and three sites in eastern Maine. Water column properties and phytoplankton was intensively examined at sites in central Maine, while sites in eastern Maine were less well characterized. Analysis of gonad indices showed that spawning was protracted in …


The Embryonic World Of Wood Frogs, Rana Sylvatica: Natal Pond Learning And Anti-Predator Behaviors., Pamela J. Bryer Jan 2002

The Embryonic World Of Wood Frogs, Rana Sylvatica: Natal Pond Learning And Anti-Predator Behaviors., Pamela J. Bryer

Electronic Theses and Dissertations

Even while in ovo many amphibians can react to the world around them, as dissolved molecules are able to pass through their protective jelly matrix and interact with developing sensory systems. Although there are many potential signals dissolved in the water, two, natal-pond recognition cues and predator recognition signals (or kairomones), have been previously shown to be relevant to several species of developing anurans. My study used natural odorants in a test of natal pond learning, and in testing both short- and long-term effects of predator chemical cues on the development and behavior of wood frog, Rana sylvatica, embryos. In …