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Full-Text Articles in Life Sciences

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 …


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 …


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 …


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, …


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 …


Fall 2002, Nsu Oceanographic Center Oct 2002

Fall 2002, Nsu Oceanographic Center

Currents

No abstract provided.


The Microbial And Metazoan Community Associated With Colonies Of Trichodesmium Spp.: A Quantitative Survey, Cc Sheridan, Deborah K. Steinberg, Gw Kling Sep 2002

The Microbial And Metazoan Community Associated With Colonies Of Trichodesmium Spp.: A Quantitative Survey, Cc Sheridan, Deborah K. Steinberg, Gw Kling

VIMS Articles

Association with resource-rich particles may benefit a number of planktonic species in oligotriphic, open-ocean regimes. This study examined communities of microbes and Zooplankton associated with colonies of the cyanobacterium Trichodesmium spp. in the Sargasso Sea. Trichodesmium colonies and seawater controls were collected near Bermuda using SCUBA during September 1995, and June, July and August 1996. Organisms associated with the colonies and those in the surrounding seawater were enumerated using light and fluorescence microscopy. We found that 85% of the Trichodesmium puff and tuft colonies examined harbored associated organisms. Associated organisms included bacteria (rod and coccoid),fungi, pennate diatoms, centric diatoms, heterotrophic …


Summer 2002, Nsu Oceanographic Center Aug 2002

Summer 2002, Nsu Oceanographic Center

Currents

No abstract provided.


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 …


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 …


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 …


Food Substrates And Digestive Capabilitites Of Marine Deposit Feeders, Lawrence M. Mayer Jul 2002

Food Substrates And Digestive Capabilitites Of Marine Deposit Feeders, Lawrence M. Mayer

University of Maine Office of Research Administration: Grant Reports

Deposit feeders play several important roles in determining whether organic material is demineralized or buried. These animals function to make surfaces available for microbial growth and move particles both horizontally and vertically within the seabed at a pace that far exceeds sedimentation. The central problem in understanding deposit feeders is to identify the materials that they utilize and to determine the sources of those materials. The interdisciplinary approach of this project is to combine a chemical reactor theory of digestion with measurements of the processing of enzymatically available amino acids, focusing on rates of hydrolysis in, and absorption from, the …


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 …


Spring 2002, Nsu Oceanographic Center Apr 2002

Spring 2002, Nsu Oceanographic Center

Currents

No abstract provided.


Fisheries Research Report No. 134, Vol 1 - Towards An Assessment Of The Natural And Human Use Impacts On The Marine Environment Of The Abrolhos Islands, F J. Webster, C J. Dibden, C F. Chubb Apr 2002

Fisheries Research Report No. 134, Vol 1 - Towards An Assessment Of The Natural And Human Use Impacts On The Marine Environment Of The Abrolhos Islands, F J. Webster, C J. Dibden, C F. Chubb

Fisheries research reports

The State Territorial Waters surrounding the Abrolhos Islands are gazetted as a Fish Habitat Protection Area and vested with the Minister for Fisheries under the Fish Resources Management Act 1994. Three Fisheries Management Papers have identified management priorities for the marine environment at the Abrolhos Islands:

  • Management of the Houtman Abrolhos System
  • Aquaculture Plan for the Houtman Abrolhos Islands
  • Sustainable Tourism Plan for the Houtman Abrolhos Islands.

These plans and other national and international obligations to examine the effect of extractive and non-extractive anthropogenic activities on marine habitats (eg. Environment Protection and Biodiversity Conservation Act 1999) led to …


Vertical Distributions Of Zooplankton At The Mouth Of Chesapeake Bay And Calibration Of Backscatter From An Acoustic Doppler Current Profiler, Arthur Keith Jenkins Apr 2002

Vertical Distributions Of Zooplankton At The Mouth Of Chesapeake Bay And Calibration Of Backscatter From An Acoustic Doppler Current Profiler, Arthur Keith Jenkins

Biological Sciences Theses & Dissertations

This study investigated the physical factors influencing the vertical distribution of zooplankton at the mouth of the Chesapeake Bay and attempted to derive biological data from acoustic Doppler current profiler (ADCP) backscatter. A single site was occupied in the North Channel at the mouth of Chesapeake Bay (37° 04' N, 75° 58' W) from 17.0–19.7 November 1999. Temperature, salinity, fluorescence, light transmission, current velocity and backscatter were measured throughout the sampling period. Plankton samples were collected every hour from 3.5, 7.5, and 11.5 m.

We found little association between ADCP backscatter and plankton concentrations, but stronger correlations between backscatter and …


Winter 2002, Nsu Oceanographic Center Jan 2002

Winter 2002, Nsu Oceanographic Center

Currents

No abstract provided.


Temporal And Spatial Variation In Reproductive Output Of The Veined Rapa Whelk (Rapana Venosa) In The Chesapeake Bay, Catherine C. Ware Jan 2002

Temporal And Spatial Variation In Reproductive Output Of The Veined Rapa Whelk (Rapana Venosa) In The Chesapeake Bay, Catherine C. Ware

Dissertations, Theses, and Masters Projects

No abstract provided.


Genetic Stock Structure Of The Sailfish, Istiophorus Platypterus, Based On Nuclear And Mitochondrial Dna, Jan Renee Mcdowell Jan 2002

Genetic Stock Structure Of The Sailfish, Istiophorus Platypterus, Based On Nuclear And Mitochondrial Dna, Jan Renee Mcdowell

Dissertations, Theses, and Masters Projects

The results of life history studies involving the sailfish, Istiophorus platypterus, from the Atlantic, Pacific, and Indian oceans were reviewed. Results of studies agree on several aspects of sailfish biology; sailfish exhibit opportunistic feeding behavior, follow the 28??C isotherm, spawn in summer mature at approximately age 3, and are the least migratory of the billfishes. However, results are in conflict concerning sex ratio and whether sailfish are single or multiple spawners. Although many researchers have reported that sailfish are sexually dimorphic, their fragile otoliths make them difficult to age, aging studies have not been validated, and sexual dimorphism has not …


Response Of Anchovy (Engaulis Ringens) Off Northern Chile To The 1997-1999 El Niño-La Niña Sequence, José L. Blanco, Patricio Barria, Jorge Castillo, Larry P. Atkinson Jan 2002

Response Of Anchovy (Engaulis Ringens) Off Northern Chile To The 1997-1999 El Niño-La Niña Sequence, José L. Blanco, Patricio Barria, Jorge Castillo, Larry P. Atkinson

CCPO Publications

No abstract provided.


The Transformation Of Iodate To Iodide In Marine Phytoplankton Cultures, George T. F. Wong, Ajcharaporn U. Piumsomboon, William M. Dunstan Jan 2002

The Transformation Of Iodate To Iodide In Marine Phytoplankton Cultures, George T. F. Wong, Ajcharaporn U. Piumsomboon, William M. Dunstan

OES Faculty Publications

Six species of phytoplankton, representing 6 major phylogenetic groups (2 oceanic species: a cyanobacteria, Synechococcus sp., and a coccolithophorid, Emiliania huxleyi; and 4 coastal species: a prasinophyte, Tetraselmis sp., the green algae Dunaliella tertiolecta, the diatom Skeletonema costatum and a dinoflagellate Amphidinium carterae) were tested for their ability to reduce iodate to iodide in batch cultures. They all did so to varying degrees. Thus, the reduction of iodate to iodide by phytoplankton may be a general phenomenon in the marine environment. At ambient concentrations of iodate, the rates of depletion of iodate and appearance of …


Phosphorus Dynamics In Cultures And Natural Populations Of Trichodesmium Spp, Margaret R. Mulholland, Sheri Floge, Edward J. Carpenter, Douglas G. Capone Jan 2002

Phosphorus Dynamics In Cultures And Natural Populations Of Trichodesmium Spp, Margaret R. Mulholland, Sheri Floge, Edward J. Carpenter, Douglas G. Capone

OES Faculty Publications

Trichodesmium spp. fix atmospheric N2 and so an element other than N limits production by these species in the oligotrophic ocean. Because dissolved inorganic phosphorus (DIP) is in short supply in many marine systems, it has been hypothesized that P is a growth-limiting nutrient for these species in nature. However, Trichodesmium is capable of hydrolyzing dissolved organic P (DOP) compounds and the inorganic products from hydrolysis may provide an additional source of P for growth. We investigated P dynamics and alkaline phosphatase activity in cultures and natural populations of Trichodesmium from the Atlantic Ocean and the north coast of …


Impact Of Sea Grass Density On Carbonate Dissolution In Bahamian Sediments, David J. Burdige, Richard C. Zimmerman Jan 2002

Impact Of Sea Grass Density On Carbonate Dissolution In Bahamian Sediments, David J. Burdige, Richard C. Zimmerman

OES Faculty Publications

Carbonate dissolution has been widely observed in shallow water tropical sediments. However, sediment budgets C have generally not been closed with respect to the amount of acid required to produce the observed carbonate dissolution. Recently it has been suggested that enhanced oxygen transport into sediments through the roots and rhizomes of sea grasses might play a role in resolving this mass balance problem. We conducted studies of sea grass-carbonate sediment interactions around Lee Stocking Island, Exuma Islands, Bahamas to further examine this problem. Our studies showed that alkalinity, total dissolved inorganic carbon (ΣCO2) and Ca2+ increased with …


Organism -Sediment Interactions: The Role Of Seabed Dynamics In Structuring The Mesohaline York River Macrobenthic Community, Elizabeth K. Hinchey Jan 2002

Organism -Sediment Interactions: The Role Of Seabed Dynamics In Structuring The Mesohaline York River Macrobenthic Community, Elizabeth K. Hinchey

Dissertations, Theses, and Masters Projects

Estuaries are dynamic physical environments. The stability of the sediment-water interface is influenced by sources and rates of sediment delivery and physical reworking of sediments by currents, tides, waves and biology, but effects of disruption of this interface on benthic biology are poorly resolved. For this study, I investigated effects of prevalent gradients in seabed disturbance processes and associated seabed characteristics on estuarine benthic community structure and function in the mesohaline York River, a tributary of Chesapeake Bay, USA. I used a variety of approaches to characterize the seabed, including sediment grain size, sediment water content, maximum depth of 7Be, …


Diet Composition Of Young-Of-The-Year Bluefish, Pomatomus Saltatrix, In The Lower Chesapeake Bay And Virginia's Coastal Ocean, James Gartland Jan 2002

Diet Composition Of Young-Of-The-Year Bluefish, Pomatomus Saltatrix, In The Lower Chesapeake Bay And Virginia's Coastal Ocean, James Gartland

Dissertations, Theses, and Masters Projects

No abstract provided.


Distribution Of The Euryhaline Squid Lolliguncula Brevis In Chesapeake Bay: Effects Of Selected Abiotic Factors, I. K. Bartol, R. Mann, M. Vecchione Jan 2002

Distribution Of The Euryhaline Squid Lolliguncula Brevis In Chesapeake Bay: Effects Of Selected Abiotic Factors, I. K. Bartol, R. Mann, M. Vecchione

Biological Sciences Faculty Publications

The majority of cephalopods are thought to have limitations arising from physiology and locomotion that exclude them from shallow, highly variable, euryhaline environments. The brief squid Lolliguncula brevis may be a notable exception because it tolerates low salinities, withstands a wide range of environmental conditions, and swims readily in shallow water. Little is known about the distribution of L. brevis in Chesapeake Bay, a diverse and highly variable estuary. Therefore, a survey of L. brevis was conducted in the Virginia portion of Chesapeake Bay from 1993 to 1997 using a 9.1 m otter trawl, and the effects of selected factors …


Comparisons Of Community Structure Between Seep And Vent Mussel-Beds, Mary Parker Turnipseed Jan 2002

Comparisons Of Community Structure Between Seep And Vent Mussel-Beds, Mary Parker Turnipseed

Dissertations, Theses, and Masters Projects

No abstract provided.


Nekton Utilization Of Intertidal Fringing Salt Marsh And Revetment Hardened Shorelines, Robert A. Carroll Jan 2002

Nekton Utilization Of Intertidal Fringing Salt Marsh And Revetment Hardened Shorelines, Robert A. Carroll

Dissertations, Theses, and Masters Projects

No abstract provided.


Microbial Ecology Of Ballast Water During A Transoceanic Voyage And The Effects Of Open-Ocean Exchange, Lisa A. Drake, Gregory M. Ruiz, Bella S. Galil, Timothy L. Mullady, Daniela O. Friedmann, Fred C. Dobbs Jan 2002

Microbial Ecology Of Ballast Water During A Transoceanic Voyage And The Effects Of Open-Ocean Exchange, Lisa A. Drake, Gregory M. Ruiz, Bella S. Galil, Timothy L. Mullady, Daniela O. Friedmann, Fred C. Dobbs

OES Faculty Publications

The only procedure used frequently to reduce the risk of invasion by ballast-mediated biota is open-ocean exchange of ballast water, a procedure in which vessels release coastal water and replace it with oceanic water. Limited information exists concerning the effects of transport upon the aquatic microbial community throughout transit and following open-ocean exchange, A transoceanic voyage aboard a commercial bulk carrier afforded us the opportunity to sample the microbial community in exchanged and unexchanged ballast-water holds during the journey from Hadera, Israel to Baltimore, USA. Five days following the exchange process, all microbial metrics tested (i.e. bacteria concentration, virus-like particle …