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Full-Text Articles in Life Sciences

Linking Bioturbation And Sensory Biology: Chemoreception Mechanisms In Deposit-Feeding Polychaetes, Sara M. Lindsay, Paul Rawson Dec 2006

Linking Bioturbation And Sensory Biology: Chemoreception Mechanisms In Deposit-Feeding Polychaetes, Sara M. Lindsay, Paul Rawson

University of Maine Office of Research Administration: Grant Reports

Soft-sediment benthic habitats are ubiquitous in the marine environment and typically feature macrofaunal assemblages that include large numbers of deposit-feeding invertebrates such as polychaetes, bivalves, gastropods, crustaceans, holothurians, and hemichordates. Via their feeding, modulated in part by chemoreception, these organisms have profound effects on the ecology, biology, geology, and chemistry of their habitats. Very little is known, however, concerning the physiology and molecular biology of chemoreception in deposit feeders.

This research is a comprehensive investigation of the sensory mechanisms coordinating chemoreception in deposit feeding spionid polychaetes. It directly addresses this lack of information and will therefore have a significant impact …


Diel And Tidal Rhythms Of Emercenge Events Based On Acousitc Observations In A Shallow Estuary, Mei Sato Dec 2006

Diel And Tidal Rhythms Of Emercenge Events Based On Acousitc Observations In A Shallow Estuary, Mei Sato

Electronic Theses and Dissertations

Field observations of emergence events by epibenthic animals were conducted with two Tracor Acoustic Profiling Systems (TAPS) in the Damariscotta River estuary, Maine, in fall 2005 and summer 2006. Spectral analysis revealed that periodic temporal variability of the acoustic signals was concentrated at four periods. One was the solar day (24 h) and the other three were lunar tidal periods of 25.82 (diurnal or Oi), 12.42 (semidiurnal or M2) and 6.21 h (half the semidiurnal period). The mysid Neomysis americana showed strong nocturnal migration patterns of water-column activity during its peak summer emergence season, regulated by the diel cycle. Toward …


Determining Environmental Drivers Of Fish Community Structure Along The Coast Of Maine, Adrian Jordaan Dec 2006

Determining Environmental Drivers Of Fish Community Structure Along The Coast Of Maine, Adrian Jordaan

Electronic Theses and Dissertations

The work presented here was conceived to determine whether structure in marine communities could be related to multiple scaled environmental parameters, as seen in lake and stream systems. Four datasets collected from 2001 to 2005 were used. The datasets ranged from local scale tidepool and estuarine surveys, to more regional intertidal/subtidal surveys and conclude using a coast-wide trawl survey. Initially, a bootstrap program for running principal component analysis (PCA) was developed and tested for utility with additional information from Pearson correlation coefficients. The bootstrap-PC A program was capable of determining confidence limits for correlations amongst species. The results from analysis …


Fall 2006, Nsu Oceanographic Center Oct 2006

Fall 2006, Nsu Oceanographic Center

Currents

No abstract provided.


Characterization Of Β-Lactam Resistant Pandemic Serotypes Of Vibrio Cholerae Isolated From Ships' Ballast Tanks And Coastal Waters, Amanda Lynn Goodrich Oct 2006

Characterization Of Β-Lactam Resistant Pandemic Serotypes Of Vibrio Cholerae Isolated From Ships' Ballast Tanks And Coastal Waters, Amanda Lynn Goodrich

OES Theses and Dissertations

Vibrio cholerae serotypes 01 and 0139 are responsible for world-wide epidemics of cholera. These pandemic causing strains must possess genes that encode for the cholera toxin (CTX) and toxin co-regulated pili (TCP) in order to infect their hosts. In this study, 284 isolates of Vibrio cholerae from ballast and coastal waters were serotyped, with 11 % testing positive for serotype 01 and 21 % testing positive for serotype 0139. PCR assays were used to detect the presence of ctxA and tcpA genes in all positive isolates, none of which contained ctxA while 2% of the isolates contained tcpA. The 01 …


Summer 2006, Nsu Oceanographic Center Aug 2006

Summer 2006, Nsu Oceanographic Center

Currents

No abstract provided.


Modeling Large Whale Entanglement Injuries: An Experimental Analysis Of The Influence Of Tissue Compliance, Line Tension, And Draw-Length On Epidermal Abrasion Resistance, Jeremy Paul Winn Aug 2006

Modeling Large Whale Entanglement Injuries: An Experimental Analysis Of The Influence Of Tissue Compliance, Line Tension, And Draw-Length On Epidermal Abrasion Resistance, Jeremy Paul Winn

Electronic Theses and Dissertations

Two test systems were developed to evaluate the influence of draw-length and tissue compliance on entanglement-induced epidermal abrasion in humpback (Megaptera novaeangliae) and right whale (Eubalaena glacialis) tissue samples. Under straight pull abrasion tests an adult right whale fluke required 3.7 times the load and 15 times the draw-length of a right whale calf flipper to induce epidermal failure while a humpback fluke was intermediate between these extremes. Epidermal thickness did not appear to be the cause of this difference in abrasion resistance. Epidermal thickness averaged 8.0k0.2 mm for the calf flipper, 4.9k0.4 rnrn for the humpback fluke, and 5.1k0.1 …


Collaborative Research: Globec-01: Tidal Front Mixing And Exchange On Georges Bank: Controls On The Production Of Phytoplankton, Zooplankton, And Larval Fishes, David W. Townsend, Robert Houghton Jul 2006

Collaborative Research: Globec-01: Tidal Front Mixing And Exchange On Georges Bank: Controls On The Production Of Phytoplankton, Zooplankton, And Larval Fishes, David W. Townsend, Robert Houghton

University of Maine Office of Research Administration: Grant Reports

Georges Bank supports a rich fishery because: (1) large portions of the bank are shallow enough that light-limitation of phytoplankton is usually not important; (2) deep waters rich in inorganic nutrients are available for mixing onto the bank; and (3) the Bank's clockwise circulation can retain the planktonic stages of important fish species. The tidally mixed front (TMF) is central to the productivity of Georges Bank through the processes of nutrient injection in the north and retention of larvae on the south flank. These two regions are connected by a circulation pathway along the front in which nutrients lead to …


Substituting Otoliths For Chemical Analyses: Does Sagitta = Lapillus?, Nathan G. Smith, Cynthia M. Jones May 2006

Substituting Otoliths For Chemical Analyses: Does Sagitta = Lapillus?, Nathan G. Smith, Cynthia M. Jones

OES Faculty Publications

Chemical analysis of fish otoliths has become an important technique in fisheries science with widespread applications. Most research up to this point has focused predominantly on sagittal otoliths, but the underlying assumptions may also apply to lapilli. The goal of this study was to determine whether lapilli and sagittae have the same otolith chemistry and whether one can be substituted for the other for solution-based chemical analysis in wild-captured fish. We compared the stable isotope chemistry (δ13C and δ18O) of paired sagittae and lapilli of juvenile spotted seatrout Cynoscion nebulosus collected from Chesapeake Bay seagrass beds in 2002. …


Biogeochemistry Of Arsenic And Antimony In The North Pacific Ocean, Gregory A. Cutter, Lynda S. Cutter May 2006

Biogeochemistry Of Arsenic And Antimony In The North Pacific Ocean, Gregory A. Cutter, Lynda S. Cutter

OES Faculty Publications

The biogeochemical cycles of the metalloid elements arsenic and antimony were examined along a 15,000 km surface water transect and at 9 vertical profile stations in the western North Pacific Ocean as part of the 2002 IOC Contaminant Baseline Survey. Results show that the speciation of dissolved arsenic (As III, As V, and methylated As) was subtly controlled by the arsenate (AsV)/phosphate ratio. An additional fraction of presumed organic arsenic previously reported in coastal waters was also present (~15% of the total As) in oceanic surface waters. Dissolved inorganic antimony displayed mildly scavenged behavior that was confirmed by correlations with …


Spring 2006, Nsu Oceanographic Center Apr 2006

Spring 2006, Nsu Oceanographic Center

Currents

No abstract provided.


The Hillarys Transect (1): Seasonal And Coss-Shelf Variability Of Physical And Chemical Water Properties Off Perth, Western Australia, 1996-98, Alan F. Pearce, M J. Lynch, Christine E. Hanson Apr 2006

The Hillarys Transect (1): Seasonal And Coss-Shelf Variability Of Physical And Chemical Water Properties Off Perth, Western Australia, 1996-98, Alan F. Pearce, M J. Lynch, Christine E. Hanson

School of Natural Sciences Publications

A 27-month study of the water properties across the continental shelf off Perth, Western Australia (the "Hillarys Transect") has provided the first systematic inter-disciplinary climatology of the physical, chemical, optical and biological cycles across the shelf. This paper describes the main features of the seasonal and cross-shelf variability of the physical oceanography and chemistry, while companion papers discuss some of the links between the biology and physics of the region


Sea Urchin Predation In Misali Island Marine Park, Nicole Esclamado Apr 2006

Sea Urchin Predation In Misali Island Marine Park, Nicole Esclamado

Independent Study Project (ISP) Collection

The populations of sea urchins and their main predators, triggerfish (Balistidae), wrasses (Labridae) and emperors (Lethrinidae), were studied in the extractive and non-extractive zones of the Misali Island Marine Conservation Area in order to (1) evaluate the applicability of a sea urchin-sea urchin predator model developed in Kenya’s fringing reefs, (2) gain baseline data on Misali’s coral reef, and (3) evaluate the recovery status of the protected zone. This study revealed the predictive power of the sea urchin-sea urchin predator model for the reef ecosystem of Misali Island. As expected, a decline in sea urchin predators as a gross trophic …


Hydrodynamic Regulation Of Reproduction In Fucoid Algae: A Regional Model And Consequences For Population Structure, Susan H. Brawley Mar 2006

Hydrodynamic Regulation Of Reproduction In Fucoid Algae: A Regional Model And Consequences For Population Structure, Susan H. Brawley

University of Maine Office of Research Administration: Grant Reports

Fucoid algae dominate most rocky shores across the north Atlantic and contribute substantially to structuring of the coastal ecosystem. Reproduction in fucoid algae is sensitive to hydrodynamic conditions, resulting in high fertilization success because gamete release occurs only under calm conditions. These findings have important implications for asynchrony in gamete release between populations and the scale of population isolation. This study will 1) test a nascent model describing when successful fucoid reproduction can occur, 2) determine whether hybridization between Fucus vesiculosus and other fucoid algae occurs when gamete release is delayed by turbulent conditions, and 3) analyze whether genetic differentiation …


Hydrographic Observations During The 2002 Ioc Contaminant Baseline Survey In The Western Pacific Ocean, C. I. Measures, Greg A. Cutter, W. M. Landing, R. T. Powell Mar 2006

Hydrographic Observations During The 2002 Ioc Contaminant Baseline Survey In The Western Pacific Ocean, C. I. Measures, Greg A. Cutter, W. M. Landing, R. T. Powell

OES Faculty Publications

The 2002 IOC Contaminant Baseline Survey in the western Pacific Ocean was the fourth in a series of cruises intended to establish the contemporary concentrations of trace elements and other materials in the major water masses of the ocean and to illuminate the pathways by which materials delivered to the surface ocean are incorporated in the subsurface waters. The expedition occupied 9 vertical profile stations encompassing the subtropical and subarctic gyre of the western North Pacific. In addition, underway surface water samples were collected during transits between the stations. This paper uses the temperature, salinity, nutrient, oxygen, and chlorophyll data …


Collaborative Research: Functional And Genomic Analysis Of Polysymbiosis In The Wood-Boring Bivalve Lyrodus Pedicellatus, Daniel L. Distel Jan 2006

Collaborative Research: Functional And Genomic Analysis Of Polysymbiosis In The Wood-Boring Bivalve Lyrodus Pedicellatus, Daniel L. Distel

University of Maine Office of Research Administration: Grant Reports

Each day massive quantities of wood and woody plant materials enter the oceans, providing resources upon which a large variety of marine organisms depend. However, the biological communities supported by marine wood are only poorly understood. Globally, the most important consumers of marine wood are wood-boring bivalves of the family Teredinidae (shipworms, primarily found above 150 m) and Pholadidae (subfamily Xylophagainae, primarily found in the deep sea, 150-8000 m). These clams depend on intracellular endosymbiotic bacteria (endocytobionts) to help them consume a substrate (lignocellulose) that cannot be utilized by most other animals. Two functions have been proposed for symbionts of …


Transport Of Antarctic Krill (Euphausia Superba) Across The Scotia Sea. Part Ii: Krill Growth And Survival, Bettina A. Fach, Eileen E. Hofmann, Eugene J. Murphy Jan 2006

Transport Of Antarctic Krill (Euphausia Superba) Across The Scotia Sea. Part Ii: Krill Growth And Survival, Bettina A. Fach, Eileen E. Hofmann, Eugene J. Murphy

CCPO Publications

A time-dependent, size-structured, physiologically based krill growth model was used in conjunction with a circulation model to test the hypothesis that Antarctic krill (Euphausia superba) populations at South Georgia are sustained by import of individuals from upstream regions. Surface phytoplankton concentrations along the simulated drifter trajectories were extracted from historical Coastal Zone Color Scanner (CZCS) measurements and sea ice biota concentrations were calculated from sea ice concentration and extent extracted along drifter trajectories from Special Sensor Microwave/ Imager measurements. As additional food sources, a time series of heterotrophic food was constructed from historical data, and time series of …


Red And Black Tides: Quantitative Analysis Of Water-Leaving Radiance And Perceived Color For Phytoplankton, Colored Dissolved Organic Matter, And Suspended Sediments, Heidi M. Dierssen, Raphael M. Kudela, John P. Ryan, Richard C. Zimmerman Jan 2006

Red And Black Tides: Quantitative Analysis Of Water-Leaving Radiance And Perceived Color For Phytoplankton, Colored Dissolved Organic Matter, And Suspended Sediments, Heidi M. Dierssen, Raphael M. Kudela, John P. Ryan, Richard C. Zimmerman

OES Faculty Publications

Using field measurements and quantitative modeling, we demonstrate that red coloration of the sea surface is not associated with any particular group of phytoplankton and is strongly dependent on the physiology of the human visual system. Red or brown surface waters can be produced by high concentrations of most types of algae, colored dissolved organic matter, or suspended sediment. Even though light reflected by red tides commonly peaks in the yellow spectral region (570–580 nm), human color perception requires consideration of the entire spectrum of light relative to receptors within the human eye. The color shift from green to red …


Size-Selectivity Of The Commercial Sea Scallop (Placopecten Magellanicus) Dredge: Evaluation The Performance Of The New Bedford Style Dredge Configured With 4-Inch Rings And A 10-Inch Twine Top Using The Select Model, Noelle Yochum Jan 2006

Size-Selectivity Of The Commercial Sea Scallop (Placopecten Magellanicus) Dredge: Evaluation The Performance Of The New Bedford Style Dredge Configured With 4-Inch Rings And A 10-Inch Twine Top Using The Select Model, Noelle Yochum

Dissertations, Theses, and Masters Projects

A size-selectivity curve was constructed to characterize the performance of the New Bedford style Atlantic sea scallop (Placopecten magellanicus) dredge when it is configured to meet the requirements of Amendment #10 to the Sea Scallop Fishery Management Plan. The curve was generated using the SELECT model on catch-at-length data, obtained by simultaneously towing a New Bedford style dredge and a non-selective National Marine Fisheries Service sea scallop survey dredge from commercial scallop vessels. Data were collected during three cruises in the Northwest Atlantic between 2005 and 2006. One cruise was completed in Georges Bank (Groundfish Closed Area II) and two …


Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman Jan 2006

Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman

Dissertations, Theses, and Masters Projects

The Chesapeake Bay spawning stock of striped bass, Morone saxatilis, is considered one of the largest sources of juvenile production along the Atlantic coast and exhibits a high degree of interannual recruitment variability. Year class strength is judged by near-shore seine surveys that cover major tributaries of Chesapeake Bay and survey results are incorporated into annual stock assessments. In these surveys, the contribution of the Rappahannock River (Virginia) to total production is significant. In this system, abundance of juveniles is highest at a single seine site, suggesting that juvenile production may be related to habitat heterogeneity and food availability. To …


Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston Jan 2006

Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston

Dissertations, Theses, and Masters Projects

No abstract provided.


A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine Jan 2006

A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine

Dissertations, Theses, and Masters Projects

No abstract provided.


Population Genetic Structure Of Escolar (Lepidocybium Flavobrunneum) And A Molecular Phylogeny Of The Trichiuroidea, Kirsten Brendtro Jan 2006

Population Genetic Structure Of Escolar (Lepidocybium Flavobrunneum) And A Molecular Phylogeny Of The Trichiuroidea, Kirsten Brendtro

Dissertations, Theses, and Masters Projects

No abstract provided.


Incorporating Space Into Stock Assessments Of Marine Species, John F. Walter Jan 2006

Incorporating Space Into Stock Assessments Of Marine Species, John F. Walter

Dissertations, Theses, and Masters Projects

Spatial management of marine resources requires population dynamic parameters in much greater spatial detail than traditional stock assessments provide. This dissertation presents a suite of methods to improve the spatial prediction of population abundance, fishing and natural mortality and to make greater use of commercial catch data. The main objectives of this dissertation are to determine the efficacy of using the vast amount of data collected by on-board observers on commercial vessels in model-based estimation of abundance and to use the spatial autocorrelation to improve resource mapping and abundance estimation. The first paper presents a methodology for improving variogram estimation …


Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke Jan 2006

Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke

Dissertations, Theses, and Masters Projects

The barndoor skate Dipturus laevis is one of seven species in the United States Northwest Atlantic skate complex. The species received little attention until a recent article published in Science reported that the barndoor skate might be on the brink of extinction. In this study, we address not only the virtual lack of information on the life history of the species, but also develop methodologies to assist in the assessment of the barndoor skate population. to investigate the life history of the species, data were collected from 2,310 specimens caught during commercial sea scallop dredging in the southern section of …


Development Of Generalized Index-Removal Models, With Particular Attention To Catchability Issues, Thomas F. Ihde Jan 2006

Development Of Generalized Index-Removal Models, With Particular Attention To Catchability Issues, Thomas F. Ihde

Dissertations, Theses, and Masters Projects

The index-removal method estimates abundance, exploitation and catchability coefficient, given surveys conducted before and after a known removal. The method assumes a closed population between surveys. Index-removal has seldom been applied due to its strong assumption of constant survey catchabilities. This work generalizes the method to allow multiple years of data to be incorporated, and the assumptions of the original model to be relaxed. If catchability is constant across years, precision can be improved by analyzing multi-year data simultaneously. Two multiple-year models were developed: the first, 1qIR, assumes constant catchability within and among years; the second, 2qIR, allows catchability to …


Development Of An Unstructured Grid, Finite Volume Eutrophication Model For The Shallow Water Coastal Bay: Application In The Lynnhaven River Inlet System, Yuepeng Li Jan 2006

Development Of An Unstructured Grid, Finite Volume Eutrophication Model For The Shallow Water Coastal Bay: Application In The Lynnhaven River Inlet System, Yuepeng Li

Dissertations, Theses, and Masters Projects

The shallow water region is an important portion of the estuarine and coastal waters, since it encompasses the entire land-water margin as the buffer zone and supports one of the most productive ecosystems. When light can penetrate to the sediment, it triggers the benthic microalgae community to perform photosynthesis, resulting in a benthic-pelagic exchange flux different from that of the deeper water. This study utilized the laboratory-measured benthic flux, and a suite of well-calibrated numerical models to examine the eutrophication process in the Lynnhaven River Inlet system with special emphasis on: the role played by benthic microalgae, and nutrient budgets …


Community Structure And Biogeography Of Mussel Bed Communities At Pacific Hydrothermal Vents: Lau And North Fiji Back-Arc Basins, 32° S---East Pacific Rise, And 38° S---Pacific Antarctic Ridge, Elizabeth Anne Blake Jan 2006

Community Structure And Biogeography Of Mussel Bed Communities At Pacific Hydrothermal Vents: Lau And North Fiji Back-Arc Basins, 32° S---East Pacific Rise, And 38° S---Pacific Antarctic Ridge, Elizabeth Anne Blake

Dissertations, Theses, and Masters Projects

No abstract provided.


Ocean Warming And Freshening In The Northern Gulf Of Alaska, Thomas C. Royer, Chester E. Grosch Jan 2006

Ocean Warming And Freshening In The Northern Gulf Of Alaska, Thomas C. Royer, Chester E. Grosch

CCPO Publications

Water column temperatures on the shelf in the northern Gulf of Alaska have increased more than 0.8 degrees C and vertical density stratification has increased since 1970 near Seward, Alaska throughout the 250 m depth. This high latitude marine system has low water temperatures, high rates of precipitation, glacial melting, high wind speeds and high rates of biological productivity. A more than 300 km alongshore shift ( locally westward) of isotherms is suggested. The observations are consistent with a conceptual ocean-atmosphere circulation model that employs coastal freshwater discharge, glacial ablation and wind forcing. Positive regional feedback mechanisms accelerate the discharge …


Vascular Morphometry Of The Retina In Antarctic Fishes Is Dependent Upon The Level Of Hemoglobin In Circulation, Jody M. Wujcik Jan 2006

Vascular Morphometry Of The Retina In Antarctic Fishes Is Dependent Upon The Level Of Hemoglobin In Circulation, Jody M. Wujcik

Electronic Theses and Dissertations

Antarctic notothenioids express the circulating oxygen-binding protein hemoglobin (Hb) over a broad range of blood concentrations. White-blooded icefishes (Suborder: Notothenioidei, Family: Channichthyidae) are the only known adult vertebrates to lack Hb completely. In addition to its role in oxygen transport, Hb is the primary reactant in degradation of nitric oxide (NO). Thus, NO should be degraded at a slower rate in Hb-lacking icefishes than in Hb-expressing notothenioids, leading to higher steady-state levels of NO in the former group. Increased levels of NO should stimulate upregulation of angiogenesis, the growth and proliferation of new blood vessels from existing vasculature. Based upon …