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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

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 …


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 …


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 …


Biogeochemical Fate Of Sediment-Associated Pah: Effect Of Animal Processing, Anders Michael Bernth Giessing Dec 2002

Biogeochemical Fate Of Sediment-Associated Pah: Effect Of Animal Processing, Anders Michael Bernth Giessing

Electronic Theses and Dissertations

Biotransformation and fate of polycyclic aromatic hydrocarbons (PAHs) in marine invertebrates and sediment have been studied. Invertebrates can accumulate and metabolize sediment-associated PAHs to polar and aqueous PAH-derived compounds. The objectives of this study are to identify metabolites of PAHs in species of depositfeeding polychaetes and to examine biogeochemical fate and microbial degradation of the identified metabolites. Two metabolites, 1-hydroxypyrene and 1-hydroxypyrene glucuronide, were identified as the primary phase I and phase II metabolites of the tetracyclic PAH pyrene in Nereis diversicolor. Identification was performed using high pressure liquid chromatography with diode array and fluorescence detection (HPLC/DAD/F) and an ion-trap …


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, …


Satellite-Measured Chlorophyll Variability Within The Upwelling Zone Near Heceta Bank, Oregon, Jennifer Bosch Dec 2002

Satellite-Measured Chlorophyll Variability Within The Upwelling Zone Near Heceta Bank, Oregon, Jennifer Bosch

Electronic Theses and Dissertations

Heceta Bank, a unique shallow bank on the southern Oregon shelf, is located within the California Current upwelling system. Four years (1998-2001) of 1-km resolution SeaWiFS ocean color satellite data of the Oregon coast are used to provide the first systematic description, and quantification of seasonal and interannual surface chlorophyll variability in the Heceta Bank region of coastal Oregon. The variability over the bank is examined with respect to wind forcing and surface temperature, and compared to the variability observed in topographically simpler shelf regions north and south of the bank. A seasonal cycle with lowest concentrations in the fall …


An Ecosystem Dynamics Model Of Monterey Bay, California, Lawrence S. Klein Aug 2002

An Ecosystem Dynamics Model Of Monterey Bay, California, Lawrence S. Klein

Electronic Theses and Dissertations

Monterey Bay is an upwelling region with high biological productivity in the California Coastal Current System. Several moorings, developed and maintained by the Monterey Bay Aquarium Research Institute (MBARI), have produced a long-term, highquality time series oceanographic data set for the Monterey Bay. The data set has revealed a more comprehensive picture of physical-biological interaction on seasonal and interannual variability. To improve our understanding of how the marine ecosystem responds to physical forcing, especially upwelling, an open ocean ecosystem model was modified for the Monterey Bay upwelling region. The result was a nine-component ecosystem model of Monterey Bay, which produced …


Suspended Alexandrium Spp. Hypnozygote Cysts In The Gulf Of Maine, Sarah L. Kirn Aug 2002

Suspended Alexandrium Spp. Hypnozygote Cysts In The Gulf Of Maine, Sarah L. Kirn

Electronic Theses and Dissertations

Hypnozygote cysts are a known stage in the life cycle of Alexandrium spp. Negatively buoyant cysts purportedly fall ,to the benthos where they undergo mandatory quiescence until their endogenous clock makes germination possible. If oxygen is present and the endogenous clock allows, germination will occur at a rate proportional to light and temperature. Offshore in the Gulf of Maine, where Alexandrium blooms are well documented, the paradigm of benthic cysts is problematic. Sediment surveys have found wide distribution of cysts, with highest cyst concentrations below 100 m in areas where deposition is favored. Germination at these depths is likely slow …


Antarctic Notothenioid Fishes Do Not Display Metabolic Cold Adaptation In Hepatic Gluconeogenesis, Leonardo J. Magnoni Aug 2002

Antarctic Notothenioid Fishes Do Not Display Metabolic Cold Adaptation In Hepatic Gluconeogenesis, Leonardo J. Magnoni

Electronic Theses and Dissertations

Antarctic notothenioid fishes present specializations related to their chronically cold environment, such as high lipid content in tissues (predominantly triacylglycerols, TAG). When TAGs are mobilized, they yield fatty acids and glycerol. Fatty acids are the primary fuel of oxidative muscle tissues. Gluconeogenesis from glycerol has not been studied in Antarctic fishes despite the importance of glycerol as a breakdown product of TAGs. To assess the possible importance of glycerol as a substrate for gluconeogenesis and to determine whether this pathway and Krebs cycle are metabolically cold adapted, key hepatic enzyme activities were measured in Antarctic notothenioid fishes (Notothenia coriiceps, Gobionotothen …


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 …


Numerical Wave Simulations On Different Oceanic Scales, Khalid M. Zubier Aug 2002

Numerical Wave Simulations On Different Oceanic Scales, Khalid M. Zubier

Electronic Theses and Dissertations

In practical applications, numerical wave models are used as reliable tools to provide near future wave predictions and wave climatology for specific region. Obviously models first should go through extensive validation/verification procedures. Once validated, models can be used in scientific applications to investigate methods for improving performance and to develop better understanding of wave associated physical mechanisms and their interactions in specific field experiments. Two wave transformation models, SWAN and CGWAVE, are used to simulate wave conditions at the Field Research Facility, Duck (North Carolina). The motivation is to examine how well these models reproduce observations and to determine the …


Arsenic In Drinking Water And Public Opinion On Wildlife Management As Case Studies Illustrating Natural Resource Policy, Jessica Sargent-Michaud Aug 2002

Arsenic In Drinking Water And Public Opinion On Wildlife Management As Case Studies Illustrating Natural Resource Policy, Jessica Sargent-Michaud

Electronic Theses and Dissertations

There are various ways to approach policy planning. This thesis consists of two Maine natural resource issue case studies illustrating different approaches to policy analysis. The first, a case study of arsenic contamination, is an example of a study that assembles information and provides that information to the public to influence public behavior. The second, a case study of wildlife management, is an example of a study that surveys the public to collect information on the public's opinions and attitudes to influence agency behavior towards the public. Arsenic in drinking water in Maine is a public health concern. There may …


Effects Of Roadway-Related Physical And Chemical Habitat Alterations On Stream Ecosystems, Thomas Stuart Woodcock Aug 2002

Effects Of Roadway-Related Physical And Chemical Habitat Alterations On Stream Ecosystems, Thomas Stuart Woodcock

Electronic Theses and Dissertations

Roadways are an important feature of both rural and urban landscapes, and disturbances associated with them have a variety of effects on stream ecosystems. Organisms may be differentially affected by toxic substances, depending on such factors as sediment and water chemistry, toxin bioavailability, uptake and elimination processes, and tolerance mechanisms. The effects of heavy metal pollution and habitat alteration related to urbanization and industry were examined along a gradient of impact in Goosefare Brook, a small stream in southern Maine with a history of water quality impahlent. The structure of invertebrate assemblages changed significantly along the gradient, and were related …


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 …


Determining Atmospheric Deposition Inputs To Two Small Watersheds At Acadia National Park, Sarah J. Nelson May 2002

Determining Atmospheric Deposition Inputs To Two Small Watersheds At Acadia National Park, Sarah J. Nelson

Electronic Theses and Dissertations

Two small upland watersheds have been gauged and monitored at Acadia National Park since 1998. Cadillac Brook watershed burned in a wildfire in 1947. Hadlock Brook watershed has been undisturbed for several centuries, and serves as the reference site. Precipitation and throughfall volume and chemistry data have been collected using wetonly and continuously open collectors. Hydrologic and chemical inputs to the sites have been determined for each site. Differences in watershed and vegetation characteristics control the input of water and major ions to these watersheds. Vegetation type was the dominant control on enhancement of precipitation across the heterogeneous watersheds. Relative …


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 …


Growth Increment Analysis Of Marine Bivalves From The North, Stephen D. Houk Jan 2002

Growth Increment Analysis Of Marine Bivalves From The North, Stephen D. Houk

Electronic Theses and Dissertations

This study aids in developing a sea surface temperature (SST) proxy with monthly temporal resolution using a combination of growth increment and stable isotope analyses of marine bivalves from the north coast of Peru. Faunal assemblages from the Siches and Ostra Base Camp archaeological sites contain shells of warm-tropical mollusks that currently live farther north in Ecuador. The presence of warm-tropical species in these sites and others as far south as 10"s latitude and dating prior to 5730 cal yr B.P. indicates a stable warm-water regime in the eastern tropical Pacific which subsequently changes to a modern temperate-water regime after …


Surficial Geology And Geomorphology Of The Western Olympus Range, Antarctica: Implications For Ice-Sheet History, Brett Vandenheuvel Jan 2002

Surficial Geology And Geomorphology Of The Western Olympus Range, Antarctica: Implications For Ice-Sheet History, Brett Vandenheuvel

Electronic Theses and Dissertations

A widespread erosion surface passes across bedrock and sedimentary deposits in the western Dry Valleys sector of the Transantarctic Mountains (TAM), southern Victoria Land, Antarctica. The surface includes stoss-and-lee slopes, channels, potholes, scoured basins, and corrugated bedrock. These features have been taken to represent subglacial meltwater erosion beneath a greatly expanded East Antarctic Ice Sheet (EAIS) in the mid-Miocene (Denton et al. 1984, Marchant et al. 1993a). Sedimentary deposits that are typically associated with ice-sheet wastage, such as outwash, are not present on the erosion surface. The lack of these deposits indicates that the expanded ice-sheet postulated to be responsible …